---
title: "1 mi² to acre = 640 acre"
description: "1 square mile is 640 acres. The arithmetic, a table of nearby values, and a converter for any other number."
url: https://atoneplace.net/convert/1-square-miles-to-acres/
site: "At One Place"
---

# 1 mi² to acre

**1 square mile in acres: 1 mi² = 640 acre**

acre = mi² × 640

1 square mile is 640 acres. To get there, multiply by 640.

## Values either side

*Square miles near 1, converted to acres.*

| Square miles | Acres |
| --- | --- |
| 0.5 mi² | 320 |
| 1 mi² ← | 640 |
| 1.5 mi² | 960 |
| 2 mi² | 1,280 |
| 2.5 mi² | 1,600 |
| 3 mi² | 1,920 |

## How the conversion works

The relationship is acre = mi² × 640. Both units measure area, so the conversion is a fixed factor that never changes.

## Common questions

### What is 1 mi² in acres?

1 mi² is 640 acre.

### How do you convert square miles to acres?

Multiply by 640.

## Related pages

- [Square miles to acres](https://atoneplace.net/convert/square-miles-to-acres/)
- [1 acre to mi²](https://atoneplace.net/convert/1-acres-to-square-miles/)
- [0.5 mi² to acre](https://atoneplace.net/convert/0-5-square-miles-to-acres/)
- [1.5 mi² to acre](https://atoneplace.net/convert/1-5-square-miles-to-acres/)
- [2 mi² to acre](https://atoneplace.net/convert/2-square-miles-to-acres/)
- [2.5 mi² to acre](https://atoneplace.net/convert/2-5-square-miles-to-acres/)
- [3 mi² to acre](https://atoneplace.net/convert/3-square-miles-to-acres/)

## Sources

- Guide for the Use of the International System of Units (SP 811) — NIST (https://www.nist.gov/pml/special-publication-811) [Public domain (US Government)]
- The International System of Units (SI Brochure) — Bureau International des Poids et Mesures (https://www.bipm.org/en/publications/si-brochure)
- Calculated on this page — At One Place (/about/)