What is 1/64 as a decimal?

1/64 is exactly 0.015625 as a decimal.

How many millimetres is 1/64 of an inch?

1/64 of an inch is 0.396875 mm, computed with the exact definition 1 inch = 25.4 mm.

1/64

Fraction1/64

Decimal0.015625

Percent1.5625%

1 of 64 equal parts filled .

Where the decimal comes from

1/64 equals 15625/1,000,000 equals 0.015625.

Multiply the top and bottom by 15625 and the denominator becomes 1,000,000. A fraction over 1,000,000 is what a decimal is: 0.015625 means 15625 thousandths.

Every way to write it

Decimal: 0.015625
Percent: 1.5625%
Ratio: 1 : 64 (part to whole)
As inches: 1/64″ = 0.396875 mm

Equivalent fractions

Multiply the top and bottom of 1/64 by the same number and the value does not change:

1/64 = 2/128 = 3/192 = 4/256 = 5/320 = 6/384 · more, or pick a denominator

On the number line

As a measurement

Read as inches, 1/64″ is 0.396875 mm exactly. The nearest marks on the finer rules:

Rule	Nearest mark	Decimal inches	mm	Difference
16ths	0″	0	0	−0.3969 mm
32ths	1/32″	0.03125	0.7938	+0.3969 mm
64ths	1/64″	0.015625	0.3969	exact

Need a different rule or a tolerance? Nearest fraction · Within tolerance

Common questions

What is 1/64 as a decimal?: 1/64 is exactly 0.015625 as a decimal.
What is 1/64 as a percentage?: 1/64 is exactly 1.5625%.
How many millimetres is 1/64 of an inch?: 1/64 of an inch is 0.396875 mm, computed with the exact definition 1 inch = 25.4 mm.

Fraction–decimal chartThe everyday set, printable.Rule charts16ths, 32nds, 64ths, 128ths.The rulerSee 1/64 in its place.

Where this comes from. Exact rational arithmetic on the values shown — fractions are pairs of integers until display, and inch–metric conversion uses 25.4 mm to the inch, exact by definition since 1959. See the full methodology.