I keep getting the red underlining in Word whenever I write the word "performant". Here I intend to refer to something that performs well or better than something else (i.e., it's more performant).

Is there something wrong with that word? Does it mean what I actually want it to say?

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    Perhaps "performant" is jargon of a particular field. If so, and you are writing for that field, then: either ignore the underline or teach Word to accept "performant".
    – GEdgar
    Commented Aug 23, 2011 at 19:11
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    I came to this discussion because I find the word performant being used more frequently. I believe it stems from the idea that optimal performance is due to a number of factors, not simply defined as speed or efficiency. If I say I want the fastest system, I might get fastest, but with substandard quality. Efficiency is closer, as it suggests the best use of resources for the desired result, but efficiency does suggest that a solution may be more concerned with cost over speed or quality. In my experience, performant suggests that there will be agreement on the appropriate tradeoffs betwee
    – user43164
    Commented Apr 24, 2013 at 22:41
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    It's jargon. Know your audience. If your audience is software engineers, it's fine. If it's anyone else, then you should either find another word or explain the jargon.
    – rich remer
    Commented Jan 28, 2015 at 4:03
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    I would use "better performance" or "better performing" rather than "more performant".
    – Toby
    Commented Nov 26, 2015 at 13:19
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    @richremer: Even some of us software engineers hate this word. It sounds like using a $5 word you don't know the meaning of instead of a 50 cent word everybody knows. Is it faster? More efficient? Quicker? Or you just think it's better and a longer buzzword will convince me? Many technical people don't like fuzzy words dressed up as technical words. Commented Sep 26, 2017 at 1:08

15 Answers 15


Whether or not "performant" is actually a real word has been debated for some time.

It does not appear in the dictionary, nor does Google definitions include it.

While it has been used before and appears in wiktionary, I would tend to avoid using it until the word becomes, well...a word.

Is there any reason you could not use one of the following instead?

Example A performed better than Example B.


Example A outperformed Example B.

Jon Galloway's blog article Performant isn't a word is an example of someone who used "performant" extensively only to be told it was not a word. While the research he did on the subject was conducted in 2007, it certainly seems to remain valid today.

  • Comments are not for extended discussion; this conversation has been moved to chat.
    – tchrist
    Commented Aug 28, 2018 at 11:45
  • As some other users have noted, performant was added to the Oxford dictionary in Dec 2018, seven years after this answer was accepted. More recent answers seem to indicate this, and anyone who wants to post a nice new clear answer should feel free to do so. OP can change their accepted checkmark (although probably won't since they haven't been here in four years), others can upvote newer answers, etc.
    – Kit Z. Fox
    Commented Mar 7, 2023 at 15:27

I use the word performant often, and its meaning (in my opinion) is subtly different from that of fast or efficient. The most performant network might not be the fastest, or the most efficient, but the one which provides the best overall service.

My IT systems are both performant and resilient.

The above seems (to me) to be very succinct. The word performant implies speed, accuracy, flexibility and capability — it implies that my IT systems are just right for my environment. They might not be the fastest, and not necessarily the most feature-packed, but they're just right for my needs.

I like performant.

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    Yeah, where I work (Melbourne, Australia, IT sector), "performant" seems to be very much a real word - I keep seeing and hearing it used by educated, native English speakers. Years ago I worked in the French IT sector, and kind of envied this word: it's very succinct to say "c'est performant mais pas chèr", but hard to translate exactly ("it's fast", "it's powerful", "it's efficient"...are not quite right). "Performant" is just the appropriate adjective for "high performance". Commented Mar 17, 2015 at 5:08
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    In my experience performant is widely used in software development environments, less so in general usage. Commented Aug 31, 2016 at 21:10
  • How do you know what performant means? Where did you look it up? Or are you just stating your own interpretation, which can, and likely is, different from those of others? Commented Sep 20, 2017 at 6:44
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    This is exactly why I hate it. The people who use it don't know what they're trying to communicate. They think it means both "might not be the fastest, or the most efficient" and "speed, accuracy, flexibility and capability" at the same time! It means both "it may not be better by every measurement but it's better overall" and "it is better by every one of these measurements"!! Commented Sep 26, 2017 at 1:32
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    "Best overall service" has to be technically defined or else it's just a subjective opinion. If one can technically define which qualities render a service "best overall", then why not do that instead of using the word "performant"? Commented Nov 13, 2017 at 21:50

It does mean what you want to say, possibly, but it's not the clearest way of saying it.

Performant is being increasingly used, therefore it deserves to be considered a word. I still have misgivings about it though, largely because it seems redundant: you could instead say "fast" or "efficient".
If something's fast, why not just say so, instead of using the word performant?
And more performant is even sillier, when you could just say faster.

At the moment, it's still the sort of word you tend to see written in press releases or spoken by marketing people. To me it's a weasel-word like "premier", which sounds promising but technically meaningless and legally non-binding (what does "premier" actually mean? First, biggest, fastest, best-selling or highest ranking sales by value?)

The word performant could mean one of several things depending on the context (fast, efficient, small, optimal) and not using one of those alternative words suggests (to me) that the speaker/writer doesn't know what he's talking about, or for some reason doesn't want me to know what he's talking about.

Go ahead and use the word if you like, but I won't trust you, because you'll sound like a sales brochure.

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    By that reasoning, everyone who uses the word "better" makes them sound like a sales brochure to you. There is a trade-off between being specific and generic. When you wish to avoid specifying the details, because both speaker and listener(s) know what is intended in the given context, it is valid to use the word performant. For instance, with regard to software code, it usually means either one or a combination of: faster processing, having more optimizations, lower memory consumption, lower filesystem usage, or being low on system resources in general.
    – Yeti
    Commented Dec 6, 2019 at 8:19
  • A query might be fast on database A and slow on database B. So is it slow or fast? It depends. If B is not actually a valid dataset the query will ever be expected to run on, then the query is "fast enough considering its intended use". It's performant.
    – Harabeck
    Commented Sep 21, 2020 at 15:19
  • And now StackExchange/Stackoverflow has jumped on the bandwagon by using this questionable word: stackoverflow.blog/2021/12/22/… Commented May 16, 2022 at 22:51
  • @Yeti in some contexts, "better" is infact a very meaningless word and definitely qualifies as a "weasel word" except when casually describing one's preference IMHO. But saying something is "better" or "more performant" is equally flimsy. It's just circular reasoning if it isn't accompanied by specific criteria (in my experience, "performant" almost never is). "Better at <x>" is relatively common, but people say "performant" specifically to avoid saying what it's performant "at". Commented Jun 14, 2022 at 20:18
  • @DarrenRinger If you're writing a scientific paper, I might agree. But even then, you might still say A is more performant than B, while referencing to a table that has all the specific data. I feel like you're just trying to point out that the word is often misused, but that does not invalidate its use. Furthermore, there is no circular reasoning here, "performant" is clearly - albeit slightly - more specific than "better", but definitively not the other way around.
    – Yeti
    Commented Jun 15, 2022 at 22:02

In French, it's an actual word that means something like performs effectively, efficiently, and well. So, French students use it regularly because it sounds like English, although I'd classify it as a false cognate.

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    According to the french Wiktionary, the french "Performant" and its related words comes from the english's "Performance", which in turn comes from old-french "Parformance"... :-) ... fr.wiktionary.org/wiki/performance
    – paercebal
    Commented Oct 26, 2014 at 19:37
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    "Performant" exists in German as well and also originates from English "Performance", which in turn became a recognized word in German in 1991. In German, something is "performant", if it has a good performance, performs well or is efficient. In no way does it imply something to be optimal.
    – Marius
    Commented Jan 14, 2015 at 23:08
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    In my opinion this is exactly the source of this annoying non-word's use. As someone who speaks fluent French (native UK English speaker) and have worked in large French companies, I have heard this used very often in French, only then to be used again in the "English" translation.
    – T9b
    Commented Oct 18, 2017 at 8:03

The word performant is engineering jargon for something that may not be objectively efficient or optimal/fast but meets the performance expectations for which it was created. When an engineer uses the word performant, they mean that it's as fast and efficient as you would intuitively expect it to be. It's not meant to declare that it's the optimal or best solution, just that after working through the problem, it's the solution he settled on, and it was as fast and efficient as he expected it to be while still remaining within other project constraints.

EDIT: Thanks to Sven for contributing a link to this page where the writers associate the degree to which an entity is performant to how well they satisfy some objective. This is very much how I've seen this word used among engineers; something is deemed performant not by merely being fast but by meeting an objective for speed.

It's all about context and connotation. If I improve part of a system that will also improve performance, I might mention in a meeting that I made the part of the system more performant, which could mean that I made it use less memory or processor time, eliminated a redundant and expensive call, used a better algorithm, replaced an external call with an internal one, the list goes on and on. But most everyone at the meeting only cares about the result, and they'll come to me afterwards to discuss the change if they are curious.

It will probably make it into the dictionaries eventually, but in the mean time there's little reason not to use the alternatives, especially since you're writing a document. If you really do want to say something is performant, you can instead outline the metrics for your comparison and use a more appropriate word like other answers have suggested. On the other hand, depending on your intended audience, throwing a buzzword like "performant" in may be helpful. Just use it with care outside of engineering circles.

For inquiring minds:

It's easy to illustrate how the word performant is used in software engineering. Consider sorting a set of numbers from smallest to greatest. Every first year Computer Science student learns the Quicksort algorithm. It is the go-to sorting algorithm because it tends to behave optimally in practice. It has a flaw, however, that can make it abysmally slow on some lists. One of the first and simplest sorting algorithms a student is introduced to, called Insertion sort, can handily beat it in some cases, even though it's usually a very bad choice of sorting algorithm (for large lists).

Which leads to a conundrum: if performant could be simply interchanged with optimal or best, which sorting algorithm would be performant: Quicksort, or Insertion sort? The answer is, "It depends."

It's that way with every algorithm. If you ask someone if their code is efficient or fast, the answer must always be "It depends." How do you define efficient? How do you define fast? And so the "made-up" or "invalid" word performant was born. It allows developers to state with certainty that given resource constraints and expectations, including how much time the developer was given to solve the problem, the proposed solution is performant. It usually implies that performance goals were taken into account, but doesn't exaggerate by saying that it is the fastest solution possible.

In some way, I think developers like to use it because the longer you write software, the humbler you become. I prefer to say that my code is performant (i.e. performance meets expectations) than to say that it is fast or the best way to handle something, because inevitably someone comes along and creates a way better than mine. It's the nature of engineering, all of us standing on the shoulders of giants. It may seem noncommittal, but what exactly do you say when you write something that you know will be obsolete months or years after it's written?

All of that said, whether it is a "word" by anyone's definition, I guarantee it will continue to be used in development circles, as it is not as interchangeable as people outside the field think.

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    You make a persuasive case for the word's utility in its originating context. My only regret is that within five years it will begin a second life in MBA-speak among people who vaguely understand it to mean "good" and who misapply to it to company strategies and sales objectives.
    – Sven Yargs
    Commented Sep 15, 2014 at 22:51
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    No, I have been a computer programmer for many years and I was just describing my experience for how the word is used among my peers. Forgive me if citations are required, I'll withdraw the answer. Commented Sep 15, 2014 at 22:52
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    Actually your definition is pretty close to the one here en.m.wiktionary.org/wiki/performant Commented Sep 15, 2014 at 22:53
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    For an example in which authors define performant in connection with three levels of success (or not) in satisfying a system objective, see this page from Reznick, Dimitrov, and Kacprzyk, Fuzzy System Design, the levels being "not performant," "partially performant," and "fully performant." This, I think, is consistent with David Schwartz's description.
    – Sven Yargs
    Commented Sep 15, 2014 at 23:07
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    How do you know what performant means? Did you look it up in a dictionary, or are you simply assuming its meaning? Commented Sep 20, 2017 at 6:50

There's not really anything inherently wrong with performant; its formation is regular enough and it seems to convey a meaning that no other single word conveys. If that is enough for you, then go ahead. But you ought to know that the word will be ill-regarded by many, who will consider it a pseudo-learned, affected, vulgar and pointless novelty. Of course, perhaps they are wrong about this, but even if so, they may well be people whose good opinion of your language is important to you.

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    +1 In my experience, the types of people who use words like "performant" don't actually care what you think of them. Commented Aug 18, 2017 at 13:58
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    ' ... it seems to convey a meaning that no other single word conveys' would suggest an obvious inherent problem. How does one find what it means if it's so rare as to not make it into a dictionary? [It has since been recognised as a neologism by an Oxford dictionary, so the major problem is now resolved.] Commented Jul 29, 2023 at 16:54

I would avoid using "performant" in any formal documentation or technical report. However -- coming from the other side of the debate -- I think that there's nothing wrong with using performant.

The English language, along with all other living languages, transform regularly. The more a word is used, the more that it will be accepted. I would be surprised, in fact, if the word doesn't hit the dictionary soon.

As long as you're in a fairly informal situation, I see nothing wrong with using the word. I agree to avoid it in anything formal, though.

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    With some misgivings, admittedly, I'm going to downvote this. Noting OP's getting the red underlining, I think we can assume he's not a native speaker. Whilst I'm happy to agree that English is a "living language", I'm not comfortable with telling non-native-speakers it's okay to promulgate any neologisms or idiosyncratic usages they happen to come up with. Commented Aug 23, 2011 at 22:05
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    Uhh... I'm a native speaker and I would totally use that phrase. :P I appreciate you're well thought out comment though. Thank you!
    – Richard
    Commented Aug 23, 2011 at 22:11
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    Well, I'm almost a "wrinkly", and ordinarily I would totally not use the word "totally" like that. In general I do agree with your basic premise, particularly when there's clear semantic space waiting to be occupied by a new usage. But in this case I'd have thought existing words like effective and efficient cover the meaning, so performant looks like a jargon "buzzword" that should be left in whatever specialised vocabularies it's already colonised. Commented Aug 23, 2011 at 22:22
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    ...anyway, having just realised that you could justifiably resent the loss of rep there, I've just been through your other answers and upvoted everything I reasonably could. You may be glad to know there was only one other I couldn't endorse, and in several cases I thought yours was the best answer, even if it didn't have the most upvotes already. Commented Aug 23, 2011 at 23:02
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    The problem is that no one knows what performant actually means. Commented Sep 20, 2017 at 6:48

To all the people saying that "performant" is not in the dictionary and it is not a word, I refer you to the Oxford English Dictionary:

A person who performs a duty, ceremony, etc., a performer.

Of course, that doesn't help back up what you've been writing, OP, but it is quite interesting.

Personally I understand your usage of "performant" just fine – as long as your audience does too, I wouldn't worry too much what the dictionary says. Maybe it'll catch on, like busting caps, moves, and rhymes.

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    How can you understand it when we have no common reference to its definition? We could use the word and have completely different interpretations or definitions of it. Commented Sep 20, 2017 at 7:11
  • Indeed, it already has a definition. Performant parallels informant, using -ant as agental suffix. Further reaching into parallels for the adjective "very much informing" leads us to informative and informatory; and by analogy, the more correct "very much performing" would be *performative or performatory -- decidedly not "performant". It aten't wot I wood of put, but if you understands it, you puts it.
    – Rich
    Commented Oct 3, 2017 at 19:48
  • The OED also recognizes the use of performant as an adjective: "That performs or operates well; functioning at a high or sophisticated level; effective." Commented Dec 6, 2019 at 1:07

I've only heard a few programmers use it. Generally in a buzzword context to imply that a piece of software or an algorithm is "not slow."


Dictionaries do not tell you which words are valid and which are not. They document the words people are using

How words get added to the Cambridge dictionary

How words get added to the Oxford dictionary

Words come into the English language in all manner of ways. The Oxford English Dictionary’s mission is to record all of these word stories, capturing their development as they continue to unfold.

Notice it doesn't say "tell you which words are valid". It says "record all of these words"

How words get added to the Merriam Webster Dictionaries

Change and variation are as natural in language as they are in other areas of human life and Merriam-Webster reference works must reflect that fact. By relying on citational evidence, we hope to keep our publications grounded in the details of current usage so they can calmly and dispassionately offer information about modern English. That way, our references can speak with authority without being authoritarian.

They are not "authoritarian" (don't tell you if a word is valid) but they are on authority on usage (this is a record of how people use this word).

So, Are people using "performant"?

Well here's Google's developer documentation showing many uses of the word

Here's Microsoft's usage of the word

Apple has plenty of usage

Checking Stack Overflow it's clear developers use this word often

As well as github users

Just searching in general brings up 19 million plus examples of usage

But if you want to claim it's not a word until some dictionary claims it is well then it's in the Cambridge English Dictionary as well as the Oxford Dictionary.

So, in answer to you question, nothing is wrong with the word "performant".

  • This should be the accepted answer now. Commented Feb 8, 2022 at 16:14

Sentences should be succinct, to the point, and should directly convey the desired meaning without ambiguity.

Performant only adds ambiguity.

For instance, what does this example sentence actually mean?

The user interface should be highly performant.

Does that mean the interface should perform well? As in, should it sing and dance? Should it be minimalist? Should it be highly responsive? Use the precise words necessary to describe the desired outcome instead of imprecise jargon that makes you seem more interested in sounding important that in getting the work done.

See this answer for further commentary.


Does it help, in the question of validity of the word, to have it referenced in Apple's iOS Human Interface Guidelines ?

"Stretching is performant, but it isn’t usually desirable for a multipixel image that can distort. Tiling is less performant than stretching, but it's the only way to achieve a textured or patterned effect."

I had to look it up, which annoyed me, though the reasons for its use (given by @david-schwartz) are compelling.

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    A perfect example of how I have no idea what they're trying to say. But BUZZ! Commented Sep 26, 2017 at 1:48
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    Yep, are they saying it's more of a performance hit, or that it's less computationally intensive? I honestly cannot tell from the isolate context. The only reason I'm here is because someone wrote in a software release note "This [new feature] provides a more performant call for iterating over a list", and the imprecision led me to google it.
    – Rich
    Commented Oct 3, 2017 at 19:45
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    @hippietrail If they said "performs well" and "does not perform as well" it would avoid any "fake words" but would be no more or less informative.
    – Casey
    Commented Dec 6, 2021 at 1:06

Acceptance of "Performant" as a word is a symptom of tautological references in the Software Engineering community.

It has been in use in Software Engineering circles since circa 1970 is slang for "efficient" or "tuned".

To answer the OP's question, "What is wrong with [it]", well, nothing really, but the above resources demonstrate that it is software engineering slang which is seldom used in publications outside of Information Technology and so hasn't been elevated to a dictionary word.

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    "Optimal" means "the best". "Performant" doesn't mean that it has the best performance, only that it has good performance. Also, just because something is annoying business-speak or tech-speak, doesn't mean that it's an "invalid" word.
    – Golden Cuy
    Commented May 25, 2014 at 11:07
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    In addition to what Andrew said, though the question is stated as "what is wrong with performant," the implication is "why isn't this word in the dictionary." So a response of "it isn't in the dictionary" (quote: "it isn't a real word") isn't an answer. Plus, you should elaborate on this "tautologic referencing in the Software Engineering community" because you haven't given enough information for me to learn anything from your answer. Commented Sep 18, 2014 at 21:25
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    It's not in the dictionary strictly because it's "new" and has mostly been used in a restricted field. Lexicographers usually watch words for a varying length of time while evaluating them before adding them to their dictionaries. Some words go viral in a short time and get in the very next edition of the dictionary, this word is taking longer. I can guarantee it will be added sooner or later to the OED, Macquarie, Webter's, etc. Just like they all have the word "crap". Commented Sep 26, 2017 at 1:52
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    It is in the dictionary, meaning "one who performs", just as informant is "one who informs". So to answer the OP's question, that's what's wrong with it. The word they're looking to coin is perhaps *performative, on the model of informative.
    – Rich
    Commented Oct 3, 2017 at 19:47

The usage I've seen of Performant means meeting expectations, working adequately, or working to specifications. It does not necessarily mean efficient or most efficient, though something that is performant could also be these things.

Thus, something is either performant or not (just as one is pregnant or not), and it's inappropriate to say something is MORE performant than something else.

A problem with using this word is it's not well known and perhaps early in its development. Future usage could easily change its meaning.


Singular synonyms may cover some cases, but they don't carry the meaning. Jon's blog tale in the accepted answer is but one of surprise and accedance. I make a case for the word performant, and detail why in this question.

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