# How to understand the process generated by transaction.duration.us？

**URL:** <https://discuss.elastic.co/t/how-to-understand-the-process-generated-by-transaction-duration-us/224510>\
**Category:** APM\
**Tags:** rum\
**Created:** [March 21, 2020, 9:02am UTC](https://discuss.elastic.co/t/how-to-understand-the-process-generated-by-transaction-duration-us/224510 "2020-03-21T09:02:22Z")\
**Posts on this page:** 4\
**Page:** 1

<div class="post-metadata">

**Author:** ![wajika](https://avatars.discourse-cdn.com/v4/letter/w/977dab/32.png) [@wajika](https://discuss.elastic.co/u/wajika)\
**Post date:** [March 21, 2020, 9:02am UTC](https://discuss.elastic.co/t/how-to-understand-the-process-generated-by-transaction-duration-us/224510/1 "2020-03-21T09:02:22Z")

</div>

Why is the [transaction.duration.us](http://transaction.duration.us) time different from the time seen on chrome devtools?  
Architecture：frontend page \> backend

---

<div class="post-metadata">

**Author:** ![vigneshshanmugam](https://sea2.discourse-cdn.com/elastic/user_avatar/discuss.elastic.co/vigneshshanmugam/32/40324_2.png) [@vigneshshanmugam](https://discuss.elastic.co/u/vigneshshanmugam)\
**Post date:** [March 23, 2020, 5:08pm UTC](https://discuss.elastic.co/t/how-to-understand-the-process-generated-by-transaction-duration-us/224510/2 "2020-03-23T17:08:20Z")

</div>

Hi @wajika,

Can you give more details on which field you are comparing the transaction with the one on chrome devtools?

We use [performance.now](https://developer.mozilla.org/en-US/docs/Web/API/Performance/now) for measuring Transaction and span timings which is used by almost all timing API's like Resource Timing, Navigation Timing etc.

Thanks,  
Vignesh

---

<div class="post-metadata">

**Author:** ![wajika](https://avatars.discourse-cdn.com/v4/letter/w/977dab/32.png) [@wajika](https://discuss.elastic.co/u/wajika)\
**Post date:** [March 30, 2020, 1:27am UTC](https://discuss.elastic.co/t/how-to-understand-the-process-generated-by-transaction-duration-us/224510/3 "2020-03-30T01:27:52Z")

</div>

![image](https://us1.discourse-cdn.com/elastic/original/3X/2/a/2ac10e2b2b7498f495eb763c79028a1095c96209.png)

---

<div class="post-metadata">

**Author:** ![system](https://us1.discourse-cdn.com/elastic/original/3X/1/a/1ac57faf039f6b580b3f104ef42a2a89e41014de.png) [@system](https://discuss.elastic.co/u/system)\
**Post date:** [April 19, 2020, 9:33pm UTC](https://discuss.elastic.co/t/how-to-understand-the-process-generated-by-transaction-duration-us/224510/4 "2020-04-19T21:33:48Z")

</div>

This topic was automatically closed 20 days after the last reply. New replies are no longer allowed.