# How to get the correct time axis when using augur refine and timetree?

**URL:** <https://nextstrain.discourse.group/t/how-to-get-the-correct-time-axis-when-using-augur-refine-and-timetree/2020>\
**Category:** Uncategorized\
**Created:** [February 3, 2026, 10:05am UTC](https://nextstrain.discourse.group/t/how-to-get-the-correct-time-axis-when-using-augur-refine-and-timetree/2020 "2026-02-03T10:05:37Z")\
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**Author:** ![jonr](https://avatars.discourse-cdn.com/v4/letter/j/6f9a4e/32.png) [@jonr](https://nextstrain.discourse.group/u/jonr)\
**Post date:** [February 4, 2026, 8:37pm UTC](https://nextstrain.discourse.group/t/how-to-get-the-correct-time-axis-when-using-augur-refine-and-timetree/2020/4 "2026-02-04T20:37:18Z")

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This works nicely, thanks!  
So `tree.nwk` output by `augur refine` already has time-calibrated branch lengths? And the `numdate` in the `branch_lengts.json` is something calculated outside of TimeTree by augur refine?

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