Relative Time Formatter
A live preview of the browser's built-in `Intl.RelativeTimeFormat`. Pick a target date and a base (default: now, updating every second), and see the formatted relative string in your chosen locale. Choose `auto` numeric to get phrasings like `yesterday` and `last week` where the language supports it, or `always` to force `1 day ago` / `1 week ago`. The unit table shows the same difference rendered as each unit — useful when picking which granularity reads best for your UI.
How to use
- Pick a target date. Leave the base on `now` for a live ticker, or uncheck to compare two fixed dates.
- Switch locale to see how Spanish, Korean, Arabic etc. render the same difference. The shape of the phrase often changes (RTL, particles, gendered nouns).
- Use the unit table to compare granularities side-by-side and pick the one that reads best in your interface.
Frequently asked questions
- What's the difference between `numeric: auto` and `always`?
- `auto` returns idiomatic phrasings when available — `yesterday` instead of `1 day ago`, `last week` instead of `1 week ago`. `always` forces the number, which is what you usually want for a literal duration display. UIs that want chat-style timestamps usually want `auto`.
- Why does the same diff give different units?
- The main output picks the largest unit where the absolute value ≥ 1 of that unit — so 90 minutes shows as `1 hour ago` even though you could also say `90 minutes ago`. The unit table lets you see every option.
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