Change Personal Timezone to UTC in Phoenix Web App Display

Matthew R. · 2025-09-23T16:54:40.392Z

Hi! Does anyone know if it's possible to change the timezone in which traces, etc are displayed in the Phoenix web app (self hosted)? Right now they are displaying in local timezone and I'd much rather have them be in UTC, which corresponds to other timestamps I have in logging and database entries. Not, I don't want to change this for everyone using that Phoenix instance. Just me! 😊

7 comments

· Sorted by Oldest

RunLLM
APP
·
·
Phoenix's web app displays trace times in your browser's local timezone and does not provide a user-specific setting to display traces in UTC; there is no built-in option to change the display timezone just for your user in a self-hosted instance. All users see times localized to their browser, and timezone customization per user is not supported in the current UI or configuration options according to official documentation and community responses. If you need UTC display, you would need to convert times manually or adjust your browser/system timezone, but this would affect all web browsing, not just Phoenix. For more details, see the discussion in the Phoenix community and documentation, which confirm this limitation and suggest that all timestamps are shown in the browser's local timezone by design, with no per-user override available at this time. Would you like more detail on possible workarounds or future roadmap? Sources: - <https://arize-ai.slack.com/archives/C04R3GXC8HK/p1752059009.769209|Slack Community Discussion>
💡 Hint: Mention RunLLM in the thread for followups.
Matthew R.
·
·
Yes, please RunLLM
RunLLM
APP
·
·
Phoenix always displays timestamps in the browser's local timezone by default, and there is currently no built-in per-user setting to display times in UTC within the web UI. This behavior is confirmed by both the Phoenix team and community: "everything in the UI gets localized to your browser’s timezone" and "Phoenix is our open source product... The docs you linked are for the Arize AX product"—the commercial version, which may have different features. There is no user preference or toggle for UTC display in the open-source Phoenix UI, and all users see times based on their browser settings, not a configurable Phoenix setting or profile option. *Workarounds:* - You can temporarily set your browser or system timezone to UTC, which will cause Phoenix (and all other sites) to display times in UTC, but this is a global change and not user-specific within Phoenix. - For programmatic access, when you export or query data via the Python client or API, timestamps are stored and returned in UTC, so you can process or display them as you wish outside the UI. - There is no current roadmap item or open feature request for per-user timezone settings in the open-source Phoenix UI. If this is important for your workflow, you may consider submitting a feature request on the <https://github.com/Arize-ai/phoenix/issues|Phoenix GitHub issues page>. *Summary of technical details:* - Timestamps are stored and processed in UTC on the backend, but the frontend (UI) uses JavaScript's `toLocaleString()` and similar methods to display times in the browser's local timezone (<https://github.com/Arize-ai/phoenix/blob/main/app/src/components/table/TimestampCell.tsx|source code example>). - There is a React hook to get the UTC offset from the browser (<https://github.com/Arize-ai/phoenix/blob/main/app/src/hooks/useUTCOffsetMinutes.ts|useUTCOffsetMinutes.ts>), but no user-facing control to override this. - The only way to see UTC in the UI is to set your browser/system timezone to UTC. Let me know if you want code snippets for exporting data in UTC or more details on how timestamps are handled internally. Sources: - <https://arize-ai.slack.com/archives/C04R3GXC8HK/p1752059009.769209|Slack Community Discussion> - <https://github.com/Arize-ai/phoenix/blob/main/app/src/components/table/TimestampCell.tsx|source code example> - <https://github.com/Arize-ai/phoenix/blob/main/app/src/hooks/useUTCOffsetMinutes.ts|useUTCOffsetMinutes.ts>
💡 Hint: Mention RunLLM in the thread for followups.
Matthew R.
·
·
That's unfortunate.
Mikyo
·
·
Hey Matthew R. your request makes sense. Feel free to file us an issue on public GitHub. We're heads down on a bunch of stuff but we might have someone pick up the issue given Phoenix is open-source.
Matthew R.
·
·
Will do, thanks Mikyo!
Matthew R.
·
·
Done: https://github.com/Arize-ai/phoenix/issues/9600
🙏1
1

RunLLM
APP
·
·
Phoenix's web app displays trace times in your browser's local timezone and does not provide a user-specific setting to display traces in UTC; there is no built-in option to change the display timezone just for your user in a self-hosted instance. All users see times localized to their browser, and timezone customization per user is not supported in the current UI or configuration options according to official documentation and community responses. If you need UTC display, you would need to convert times manually or adjust your browser/system timezone, but this would affect all web browsing, not just Phoenix. For more details, see the discussion in the Phoenix community and documentation, which confirm this limitation and suggest that all timestamps are shown in the browser's local timezone by design, with no per-user override available at this time. Would you like more detail on possible workarounds or future roadmap? Sources: - <https://arize-ai.slack.com/archives/C04R3GXC8HK/p1752059009.769209|Slack Community Discussion>
💡 Hint: Mention RunLLM in the thread for followups.
Matthew R.
·
·
Yes, please RunLLM
RunLLM
APP
·
·
Phoenix always displays timestamps in the browser's local timezone by default, and there is currently no built-in per-user setting to display times in UTC within the web UI. This behavior is confirmed by both the Phoenix team and community: "everything in the UI gets localized to your browser’s timezone" and "Phoenix is our open source product... The docs you linked are for the Arize AX product"—the commercial version, which may have different features. There is no user preference or toggle for UTC display in the open-source Phoenix UI, and all users see times based on their browser settings, not a configurable Phoenix setting or profile option. *Workarounds:* - You can temporarily set your browser or system timezone to UTC, which will cause Phoenix (and all other sites) to display times in UTC, but this is a global change and not user-specific within Phoenix. - For programmatic access, when you export or query data via the Python client or API, timestamps are stored and returned in UTC, so you can process or display them as you wish outside the UI. - There is no current roadmap item or open feature request for per-user timezone settings in the open-source Phoenix UI. If this is important for your workflow, you may consider submitting a feature request on the <https://github.com/Arize-ai/phoenix/issues|Phoenix GitHub issues page>. *Summary of technical details:* - Timestamps are stored and processed in UTC on the backend, but the frontend (UI) uses JavaScript's `toLocaleString()` and similar methods to display times in the browser's local timezone (<https://github.com/Arize-ai/phoenix/blob/main/app/src/components/table/TimestampCell.tsx|source code example>). - There is a React hook to get the UTC offset from the browser (<https://github.com/Arize-ai/phoenix/blob/main/app/src/hooks/useUTCOffsetMinutes.ts|useUTCOffsetMinutes.ts>), but no user-facing control to override this. - The only way to see UTC in the UI is to set your browser/system timezone to UTC. Let me know if you want code snippets for exporting data in UTC or more details on how timestamps are handled internally. Sources: - <https://arize-ai.slack.com/archives/C04R3GXC8HK/p1752059009.769209|Slack Community Discussion> - <https://github.com/Arize-ai/phoenix/blob/main/app/src/components/table/TimestampCell.tsx|source code example> - <https://github.com/Arize-ai/phoenix/blob/main/app/src/hooks/useUTCOffsetMinutes.ts|useUTCOffsetMinutes.ts>
💡 Hint: Mention RunLLM in the thread for followups.
Matthew R.
·
·
That's unfortunate.
Mikyo
·
·
Hey Matthew R. your request makes sense. Feel free to file us an issue on public GitHub. We're heads down on a bunch of stuff but we might have someone pick up the issue given Phoenix is open-source.
Matthew R.
·
·
Will do, thanks Mikyo!
Matthew R.
·
·
Done: https://github.com/Arize-ai/phoenix/issues/9600
🙏1
1