What Is a Dunam?

The dunam (also spelled dönüm, donum, or dunum) is a unit of land area that originated in the Ottoman Empire and remains in active use across the Middle East, Turkey, Israel, Palestine, Jordan, and Cyprus. Understanding how to convert dunams to acres — and vice versa — is essential for anyone dealing with land in these regions.

The Modern Dunam: Standard Definition

While historical variations existed, the modern metric dunam is now internationally recognized as exactly:

  • 1 dunam = 1,000 square meters
  • 1 dunam = 0.1 hectares
  • 1 dunam = 0.247105 acres

This means roughly 4.047 dunams equal 1 acre, or more precisely: 1 acre = 4.04686 dunams.

Dunam to Acres Conversion Table

DunamsAcresSquare Meters
10.2471,000
20.4942,000
51.2365,000
102.47110,000
204.94220,000
5012.35550,000
10024.711100,000
500123.553500,000

Acres to Dunams Conversion Table

AcresDunamsSquare Meters
0.52.0232,023
14.0474,047
28.0948,094
520.23420,234
1040.46940,469
25101.171101,171
100404.686404,686

How to Convert: The Simple Formula

Converting between dunams and acres is straightforward once you know the multiplier:

  1. Dunams → Acres: Multiply dunams × 0.247105
  2. Acres → Dunams: Multiply acres × 4.04686
  3. Dunams → Square Meters: Multiply dunams × 1,000
  4. Dunams → Hectares: Multiply dunams × 0.1

Practical Examples

Example 1: Buying Agricultural Land

A plot listed as 12 dunams in the Jordan Valley. In familiar units: 12 × 0.247 = 2.96 acres, or 12,000 square meters.

Example 2: Reading an Israeli Property Listing

A property near Tel Aviv is advertised as 3.5 dunams. That converts to: 3.5 × 1,000 = 3,500 square meters, or about 0.865 acres.

Example 3: Turkish Land Purchase

In Turkey, land is sometimes still discussed in dönüm. A 20-dönüm plot = 20,000 sq meters = 4.94 acres.

Watch Out for the "Old Dunam"

Before metric standardization, the Ottoman dunam measured approximately 919–940 square meters depending on the region. If you're reviewing older property deeds or historical documents, be aware that figures may be based on the pre-metric standard. Always confirm which definition applies when reviewing historical land records.

Key Takeaways

  • 1 modern dunam = exactly 1,000 sq meters = 0.247 acres
  • 4 dunams ≈ 1 acre (more precisely: 4.047)
  • Always check whether historical documents use Ottoman or metric dunam
  • The dunam is the standard unit in Israeli, Palestinian, and Jordanian land law