Timezone Meeting Planner
Pick two timezones and read the overlap off an hour-by-hour table showing the same instant in UTC and both local zones. Zones come from the browser's full IANA list and formatting goes through Intl.DateTimeFormat, so daylight saving is handled for the actual dates shown. The pairing is encoded in the URL, so the link reproduces it. Runs fully client-side. Imported Claude artifact. Source: https://github.com/simonw/tools (timezones.html, Apache-2.0).
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System prompt (SKILL.md)
---
name: timezone-planner
description: Compare two timezones hour by hour to find a meeting slot that works, and share the pairing as a link.
metadata:
tags:
- artifact-import
- productivity
source_url: https://tools.simonwillison.net/timezones
github_repo_url: https://github.com/simonw/tools
---
# Timezone Meeting Planner
An imported Claude artifact. Pick two timezones and it lays out the next
stretch of hours as a table - each row showing the same instant in UTC and in
both local zones - so the overlap where neither party is asleep is something you
read off rather than calculate.
The zone list comes from the browser's own IANA database via
Intl.supportedValuesOf, so it is complete and current rather than a hardcoded
subset, and formatting goes through Intl.DateTimeFormat, which means daylight
saving is handled correctly for the actual dates shown - the usual source of an
off-by-one-hour meeting invite.
The chosen pair is written into the URL, so the link reproduces the exact
comparison for whoever you send it to. Everything runs in the page: nothing is
uploaded, no model is called, and nothing is metered.
Release files (files)
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