Length · Unit Converter

Convert Rod to Microinch

Convert rods to microinches instantly. 1 rod = 1.98e+8 microinch — use the live calculator, the exact formula, a conversion table and worked examples. Also check the Microinch to Rod 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

Rod

What is a rod?

A rod is an Imperial unit of length equal to 16.5 feet (about 5.03 m). It is also called a perch or pole. Used historically in English and American land surveying.

Origin of the rod

The rod derives from medieval English land-surveying practice. Standardised at 16.5 feet (= 25 links of a surveyor's chain = 1/4 chain) by Edmund Gunter in 1620.

Where it is used

Rods are the standard unit in legacy US public-land-survey records, where lot dimensions are typically expressed in rods and chains. Modern surveyors generally use feet or meters but legacy deeds remain in rods.

When and where it was developed

Defined by Edmund Gunter in 1620 as 16.5 feet via the chain-based survey system; became exact via the 1959 International Yard and Pound Agreement.

Imperial / US Customary

Microinch

What is a microinch?

A microinch is an Imperial unit of length equal to one millionth of an inch (2.54×10⁻⁸ m). It is used almost exclusively in surface-finish specifications for precision machining and optical components.

Origin of the microinch

The microinch is derived from the inch using the SI-style prefix micro- to denote one millionth. Standardised through the 1959 International Yard and Pound Agreement, which fixed the inch at exactly 25.4 mm.

Where it is used

Microinches express surface roughness (Ra values) in US-based precision manufacturing — typical machined surfaces are 16–125 µin. Optical components and bearing races are often specified to 1–4 µin Ra.

When and where it was developed

Used in US precision-manufacturing literature throughout the 20th century; value became exact in 1959 when the inch was fixed at 25.4 mm via the International Yard and Pound Agreement.

Rod to Microinch conversion formula

The relationship between rods and microinches:

1 rd = 1.98e+8 µin
1 µin = 5.050505e-9 rd

To convert rods to microinches, multiply the value in rods by 1.98e+8. To reverse, multiply microinches by 5.050505e-9.

How to use this converter

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

Step-by-step: convert rods to microinches

  1. Write down the value in rods (rd).
  2. Multiply that value by the factor 1.98e+8.
  3. The product is the equivalent value in microinches (µin).
  4. To reverse, multiply the microinch value by 5.050505e-9.

Worked examples

Example 1 — Convert 1 rd to µin:
1 × 1.98e+8 = 1.98e+8 µin

Example 2 — Convert 100 rd to µin:
100 × 1.98e+8 = 1.98e+10 µin

Real-world example — Human-scale to atomic dimensions

One rod equals one billion microinches — the canonical metric conversion bridging everyday objects and atomic-scale features in physics, chemistry, and electronics.

1 rd × 1.98e+8 = 1.98e+8 µin

Real-world example — Meter to nanoscale

One rod equals one billion microinches. Physics curricula use this conversion to teach orders of magnitude when introducing the electromagnetic spectrum.

1 rd × 1.98e+8 = 1.98e+8 µin

Rod to Microinch conversion table

Standard reference values for converting rods to microinches:

Rod [rd]Microinch [µin]
0.011980000.0000000002
0.11.98e+7
11.98e+8
23.96e+8
35.94e+8
47.92e+8
59.9e+8
101.98e+9
203.96e+9
305.94e+9
407.92e+9
509.9e+9
1001.98e+10
5009.9e+10
10001.98e+11

Frequently asked questions

How many microinches is 1 rod?
1 rod equals 1.98e+8 microinch.
How do I convert rods to microinches?
Multiply the value in rods by 1.98e+8 to get microinches.
How do I convert microinches back to rods?
Multiply the value in microinches by 5.050505e-9, or use the Microinch to Rod converter.
How many microinches is 100 rods?
100 rods equals 1.98e+10 microinches, because 100 × 1.98e+8 = 1.98e+10.

Convert Rod to other length units

Show all Rod conversions

Sources & references

Conversion factor (1 rd = 1.98e+8 µin) verified against the following authoritative sources:

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