Length · Unit Converter

Convert Chō to Dunam (Ottoman)

Convert chōs to dunams instantly. 1 chō = 7.4131858275 dunam (ottoman) — use the live calculator, the exact formula, a conversion table and worked examples. Also check the Dunam (Ottoman) to Chō converter for the reverse conversion.

Written by Sunith Babu L, Ph.D., Lead Engineer Reviewed by Girish V Kulkarni Ph.D.
Length category 2 min read Published Last reviewed Updated

Units explained

Other Regional

Chō

What is a chō?

A chō is a Japanese unit of large-scale area equal to approximately 9917.36 m² (about 0.991 hectare or 2.45 acres). It equals 3,000 tsubo.

Origin of the chō

Traditional Japanese land area unit, used historically for rice paddies and large estates.

Where it is used

Chōs appear in Japanese agricultural records and historical land documents. Modern usage favors hectares for new transactions but legacy records remain.

When and where it was developed

Traditional Japanese unit; standardized via the tsubo definition.

Other Regional

Dunam (Ottoman)

What is a dunam (ottoman)?

An Ottoman dunam was a historical unit of area used across the Ottoman Empire, approximately 1337.8 m². The value varied somewhat by region.

Origin of the dunam (ottoman)

Originated as the area a yoke of oxen could plow in a day, a measure used across much of the Mediterranean. Standardized in different regional ways.

Where it is used

Ottoman dunams appear in pre-20th-century land records across the former Ottoman Empire. Modern usage has shifted to metric dunams (exactly 1000 m²).

When and where it was developed

Traditional Ottoman unit; largely superseded by metric dunam.

Chō to Dunam (Ottoman) conversion formula

The relationship between chōs and dunams:

1 chō = 7.4131858275 dunam
1 dunam = 0.1348947704 chō

To convert chōs to dunams, multiply the value in chōs by 7.4131858275. To reverse, multiply dunams by 0.1348947704.

How to use this converter

Type a value into the calculator. The result in dunams updates as you type. Tap a quick value, copy the result with one click, or use the swap arrow to jump straight to the Dunam (Ottoman) to Chō converter for the reverse direction.

Step-by-step: convert chōs to dunams

  1. Write down the value in chōs (chō).
  2. Multiply that value by the factor 7.4131858275.
  3. The product is the equivalent value in dunams (dunam).
  4. To reverse, multiply the dunam (ottoman) value by 0.1348947704.

Worked examples

Example 1 — Convert 1 chō to dunam:
1 × 7.4131858275 = 7.4131858275 dunam

Example 2 — Convert 100 chō to dunam:
100 × 7.4131858275 = 741.3185827478 dunam

Real-world example — Maritime exclusion zone

A 200-chō exclusion zone (a common maritime boundary) converts to a different value in dunams that's useful when describing the same zone in everyday land-distance units.

200 chō × 7.4131858275 = 1482.6371654956 dunam

Real-world example — Coastal cruise distances

A 10-chō coastal sailing route converts to a different value in dunams — useful for cruise operators who switch between maritime, aviation, and road-distance units depending on the leg of the trip.

10 chō × 7.4131858275 = 74.1318582748 dunam

Real-world example — Road-sign distances across systems

A 100-chō road sign converts cleanly into dunams — exactly the conversion drivers planning trips abroad rely on when reading road signs in a different measurement system.

100 chō × 7.4131858275 = 741.3185827478 dunam

Chō to Dunam (Ottoman) conversion table

Standard reference values for converting chōs to dunams:

Chō [chō]Dunam (Ottoman) [dunam]
0.010.0741318583
0.10.7413185827
17.4131858275
214.826371655
322.2395574824
429.6527433099
537.0659291374
1074.1318582748
20148.2637165496
30222.3955748243
40296.5274330991
50370.6592913739
100741.3185827478
5003706.592913739
10007413.1858274779

Frequently asked questions

How many dunams is 1 chō?
1 chō equals 7.4131858275 dunam (ottoman).
How do I convert chōs to dunams?
Multiply the value in chōs by 7.4131858275 to get dunams.
How do I convert dunams back to chōs?
Multiply the value in dunams by 0.1348947704, or use the Dunam (Ottoman) to Chō converter.
How many dunams is 100 chōs?
100 chōs equals 741.3185827478 dunams, because 100 × 7.4131858275 = 741.3185827478.

Convert Chō to other area units

Show all Chō conversions

Sources & references

Conversion factor (1 chō = 7.4131858275 dunam) verified against the following authoritative sources:

Results are provided for general reference. Verify critical measurements against an authoritative standard.