Percentile meaning and what it actually shows

Hello, i’m struggling to understand metric called percentile, tried googling it and so on. But it is hard to grasp what are those timings we get with api tests. As I though at first that i.e. 90th percentile metric shows that 10% of API tests, have 1.935 duration, but I am not sure anymore. And if I am right, how does it actually get the percentile ?

It’s 90th percentile. It means that 90% of the requests should be faster than given latency, in your case 1.935 seconds I believe. In other words only 10% of the requests are allowed to be slower than this time.

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A small correction to

It means that 90% of the requests should be faster than given latency, in your case 1.935 seconds I believe. In other words only 10% of the requests are allowed to be slower than this time.

In this context(k6 showing some percentiles) it means that 90% of the requests were not should.

If this was about k6 thresholds using percentiles - then yes it will be about what is allowed for the test to pass.

And if I am right, how does it actually get the percentile ?

Basically what it says in Percentile - Wikipedia

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