# Ordinal Number Converter

> Convert numbers to ordinals — 1st, first, primary, Roman — with the irregular cases right.

English ordinals take st, nd or rd after 1, 2 and 3 — except for 11, 12 and 13, which take th despite their final digit. That exception repeats every hundred, so 111 is 111th but 121 is 121st. This converter handles it, along with written-out words and Roman numerals.

**URL:** https://convertto.tech/t/ordinal-number-converter
**Category:** Number Tools (https://convertto.tech/c/number-tools)
**Privacy:** Runs entirely in the browser; no upload
**Cost:** Free, no sign-up
**Last updated:** 2026-08-01

## Key facts

- **Privacy:** Runs entirely in your browser — nothing is uploaded
- **Cost:** Free, unlimited, no sign-up

## How to use

1. Enter or paste your numbers.
2. Choose the convert to.
3. Choose the language.
4. The result appears immediately — copy or download it.

## FAQ

### Why is it 11th and not 11st?

Because 11, 12 and 13 are exceptions that take "th" despite their final digits. The rule repeats every hundred, so 111 is 111th while 121 is 121st — which is why naive suffix code gets it wrong.

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