HomeUnit Conversion › Square feet to Acres

Square feet to Acres (ft² to acre)

Convert square feet to acres: 1 ft² = 0.0000229568 acre. Exact conversion factor, formula, 22-row table and worked examples, with JSON API and MCP access.

Formula

1 ft² = 0.0000229568 acre

acres = square feet × 0.00002295684114 — reverse: square feet = acres × 43560

The factor is derived from the SI definitions of both units (base unit: m2) as listed in NIST SP 811; results on this page are shown to 6 significant figures, the API returns up to 12.

Worked examples

Square feet to acres conversion table

Square feet (ft²)Acres (acre)
10.0000229568
20.0000459137
30.0000688705
40.0000918274
50.000114784
60.000137741
70.000160698
80.000183655
90.000206612
100.000229568
150.000344353
200.000459137
250.000573921
300.000688705
400.000918274
500.00114784
750.00172176
1000.00229568
2000.00459137
2500.00573921
5000.0114784
10000.0229568

FAQ

How many acres are in one square foot?

1 ft² = 0.0000229568 acre. The factor comes from the SI definitions of both units (NIST SP 811 / BIPM), so it is exact or correct to at least 10 significant figures.

What is the formula to convert square feet to acres?

Multiply the value in square feet by 0.00002295684114: acres = square feet × 0.00002295684114. For example, 5 ft² = 0.000114784 acre.

How do I convert acres back to square feet?

Multiply by the inverse factor 43560 (square feet = acres × 43560), or use the acres-to-square feet page.

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