Square Foot to Acre

Free instant square foot to acre converter. 1 ft² = 2.2957e-5 ac.

2.2957e-5
Formula
1 ft² = 2.2957e-5 ac

Common Square Foot to Acre values

Square Foot (ft²)Acre (ac)
12.2957e-5
50.000114784
100.000229568
250.000573921
500.00114784
1000.00229568
5000.0114784
10000.0229568

How does Square Foot to Acre conversion work?

Type a value in the Square Foot (ft²) field and the equivalent in Acre (ac) appears instantly to the right. The math uses the exact formula shown above — no rounding errors, no approximations beyond standard floating-point precision. Use the swap button to flip the units and see the inverse conversion.

Square Foot. The standard floor-area unit in the US. About a quarter of a square metre.

Acre. The traditional land-area unit in the US, UK, and many former British colonies. About 4,047 square metres.

⚡ Instant results

No submit button — the result updates as you type. Math runs entirely in your browser, so it’s as fast as your device.

📱 Use on any device

Works in any modern browser — Mac, Windows, Linux, iPhone, Android, tablets. No installation, no signup.

🎯 Accurate conversions

Conversion factors come from the official standard (NIST, BIPM, ISO definitions where applicable). Values are precise to standard floating-point limits.

🎁 Always free, no signup

Free, every time. No account, no email, no “trial” that becomes paid. Ad-supported so you never have to pay.

Frequently asked

What is the formula for converting Square Foot to Acre?+
The formula is: 1 ft² = 2.2957e-5 ac. Type any value into the calculator above and the result appears instantly.
How do I convert Acre back to Square Foot?+
Click the swap button (⇄) above to go to the Acre → Square Foot converter, or use the inverse formula derived from the one shown.

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