Google Colab Runtime Timezone – No Persistent TZ Setting

Runtime Timezone Configuration

Google Colab runs on an Ubuntu VM whose system clock is fixed to UTC. The Python datetime library defaults to UTC unless the TZ environment variable is overridden. While users can temporarily set os.environ['TZ'] = 'Area/Location' or export TZ in a shell, this change does not persist across runtime restarts and does not affect services that rely on the system clock, such as GPU driver timestamps or external API calls.

Notebook UI timestamps (execution history, last‑modified) are rendered in the browser’s local time via JavaScript, converting from UTC. This leads to a mismatch when the runtime log appears to use a different zone than the UI, confusing users who assume the runtime reflects their local zone.

Despite these gaps, Colab offers no user‑visible configuration to set or persist a custom timezone. The current behavior leaves users uncertain about how to reliably handle regional dates in notebooks.

What mechanisms could Colab introduce to allow a persistent timezone setting across session restarts? How would such a feature interact with external services that expect UTC timestamps? Could the UI be extended to display the runtime’s actual timezone instead of always converting to the browser’s local time?