Length · Unit Converter

Convert Rood to Square Thou

Convert roods to square thous instantly. 1 rood = 1.56816e+12 square thou — use the live calculator, the exact formula, a conversion table and worked examples. Also check the Square Thou to Rood 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

Imperial / US Customary

Rood

What is a rood?

A rood is an imperial unit of area equal to approximately 1011.71 m², or 1/4 of an acre. It was historically used in England and parts of the British Empire.

Origin of the rood

Defined as one-quarter of an acre; historically used in medieval English farming as the area one ox could plow in a day. The word relates to 'rod' as a measure of length used in plot dimensions.

Where it is used

Roods appear in historical English farming records, parish records, and old property deeds. The unit is functionally obsolete today.

When and where it was developed

Medieval English farming origin; standardized via the 1959 International Yard and Pound Agreement.

Imperial / US Customary

Square Thou

What is a square thou?

A square thou is an imperial unit of area equal to 6.4516×10⁻¹⁰ m², identical to the square mil. The word 'thou' is short for 'thousandth' (of an inch).

Origin of the square thou

Identical in value to the square mil; 'thou' is the British engineering term, 'mil' is the American term. Both refer to 1/1000 of an inch.

Where it is used

Square thous are used in British and Commonwealth engineering contexts where 'thou' is preferred over 'mil', particularly in mechanical engineering tolerance specifications.

When and where it was developed

Standardized via the 1959 International Yard and Pound Agreement.

Rood to Square Thou conversion formula

The relationship between roods and square thous:

1 rood = 1.56816e+12 thou²
1 thou² = 6.3769e-13 rood

To convert roods to square thous, multiply the value in roods by 1.56816e+12. To reverse, multiply square thous by 6.3769e-13.

How to use this converter

Type a value into the calculator. The result in square thous updates as you type. Tap a quick value, copy the result with one click, or use the swap arrow to jump straight to the Square Thou to Rood converter for the reverse direction.

Step-by-step: convert roods to square thous

  1. Write down the value in roods (rood).
  2. Multiply that value by the factor 1.56816e+12.
  3. The product is the equivalent value in square thous (thou²).
  4. To reverse, multiply the square thou value by 6.3769e-13.

Worked examples

Example 1 — Convert 1 rood to thou²:
1 × 1.56816e+12 = 1.56816e+12 thou²

Example 2 — Convert 100 rood to thou²:
100 × 1.56816e+12 = 1.56816e+14 thou²

Real-world example — Geographic to wavelength scale

One rood equals one trillion square thous — illustrating the 12-order-of-magnitude span between geographic distance and atomic-feature scales.

1 rood × 1.56816e+12 = 1.56816e+12 thou²

Real-world example — Kilometres to wavelengths

One rood equals one trillion square thous — a conversion physics teachers use to convey the gulf between everyday geographic and atomic scales.

1 rood × 1.56816e+12 = 1.56816e+12 thou²

Rood to Square Thou conversion table

Standard reference values for converting roods to square thous:

Rood [rood]Square Thou [thou²]
0.011.56816e+10
0.11.56816e+11
11.56816e+12
23.13632e+12
34.70448e+12
46.27264e+12
57.8408e+12
101.56816e+13
203.13632e+13
304.70448e+13
406.27264e+13
507.8408e+13
1001.56816e+14
5007.8408e+14
10001.56816e+15

Frequently asked questions

How many square thous is 1 rood?
1 rood equals 1.56816e+12 square thou.
How do I convert roods to square thous?
Multiply the value in roods by 1.56816e+12 to get square thous.
How do I convert square thous back to roods?
Multiply the value in square thous by 6.3769e-13, or use the Square Thou to Rood converter.
How many square thous is 100 roods?
100 roods equals 1.56816e+14 square thous, because 100 × 1.56816e+12 = 1.56816e+14.

Convert Rood to other area units

Show all Rood conversions

Sources & references

Conversion factor (1 rood = 1.56816e+12 thou²) verified against the following authoritative sources:

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