Millisecond Converter
Paste a bare millisecond duration from a log or benchmark and read it back as seconds, minutes, hours, days and weeks, plus a clock-style h:mm:ss.ms breakdown. Accepts numbers as you copy them - commas and underscores are stripped - and rejects non-numeric input rather than showing NaN. Runs fully client-side. Imported Claude artifact. Source: https://github.com/simonw/tools (milliseconds.html, Apache-2.0).
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Details
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System prompt (SKILL.md)
---
name: millisecond-converter
description: Paste a duration in milliseconds and read it back as seconds, minutes, hours, days and weeks, plus a clock-style breakdown.
metadata:
tags:
- artifact-import
- dev-tools
source_url: https://tools.simonwillison.net/milliseconds
github_repo_url: https://github.com/simonw/tools
---
# Millisecond Converter
An imported Claude artifact for the moment a log line or a benchmark hands you
a bare number like 187238 and you have to work out whether that is three
minutes or three hours. Paste it and every unit appears at once - seconds,
minutes, hours, days, weeks - alongside a clock-style hours:minutes:seconds.ms
breakdown.
It accepts numbers the way you actually copy them: commas and underscores are
stripped, so 187,238 and 187_238 both parse. Non-numeric input is rejected with
a clear message rather than silently producing NaN.
Conversion runs as you type. Nothing is uploaded, no model is called, and
nothing is metered.
Release files (files)
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