What is 0.64 as a fraction?

0.64 as a fraction is 16/25. Write the digits over 100 to get 64/100, then divide top and bottom by 4.

What is 0.64 as a percentage?

0.64 is 64%. Multiplying a decimal by 100 moves the point two places to the right.

How many millimetres is 0.64 of an inch?

0.64 inches is 16.256 mm, using the exact definition 1 inch = 25.4 mm.

0.64 as a fraction

Fraction16/25lowest terms

Decimal0.64

Percent64%

How to get there

0.64 has 2 digits after the point, so it is that many hundredths: write the digits over 100 — 64/100.
64 and 100 share a greatest common divisor of 4. Divide both by it: 16/25.

64 of 100 squares — 0.64 of the whole, which is also 64%.

As a measurement

Read as inches, 0.64″ is 16.256 mm exactly. The nearest marks on a rule:

Rule	Nearest mark	Inches	mm	Difference
16ths	5/8″	0.625	15.875	−0.381 mm
32ths	5/8″	0.625	15.875	−0.381 mm
64ths	41/64″	0.640625	16.2719	+0.0159 mm

Common questions

What is 0.64 as a fraction?: 0.64 as a fraction is 16/25. Write the digits over 100 to get 64/100, then divide top and bottom by 4.
What is 0.64 as a percentage?: 0.64 is 64%. Multiplying a decimal by 100 moves the point two places to the right.
How many millimetres is 0.64 of an inch?: 0.64 inches is 16.256 mm, using the exact definition 1 inch = 25.4 mm.

The same number, other ways

16/25Everything about the fraction: equivalents, the bar model, the number line.64%The same value as a percentage, with its own derivation.Decimal → fraction chartThe whole lookup table, printable.Nearest fractionMatch 0.64″ against any rule, with the exact error.

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.