What is 21/25 as a decimal?

21/25 is exactly 0.84 as a decimal.

How many millimetres is 21/25 of an inch?

21/25 of an inch is 21.336 mm, computed with the exact definition 1 inch = 25.4 mm.

21/25

Fraction21/25

Decimal0.84

Percent84%

21 of 25 equal parts filled .

Where the decimal comes from

21/25 equals 84/100 equals 0.84.

Multiply the top and bottom by 4 and the denominator becomes 100. A fraction over 100 is what a decimal is: 0.84 means 84 hundredths.

84 of 100 squares — 0.84 of the whole. The same squares read as a percentage: 84%, because percent means per hundred.

Every way to write it

Decimal: 0.84
Percent: 84%
Ratio: 21 : 25 (part to whole)
As inches: 21/25″ = 21.336 mm

Equivalent fractions

Multiply the top and bottom of 21/25 by the same number and the value does not change:

21/25 = 42/50 = 63/75 = 84/100 = 105/125 = 126/150 · more, or pick a denominator

On the number line

As a measurement

Read as inches, 21/25″ is 21.336 mm exactly. The nearest marks on the finer rules:

Rule	Nearest mark	Decimal inches	mm	Difference
16ths	13/16″	0.8125	20.6375	−0.6985 mm
32ths	27/32″	0.84375	21.4313	+0.0953 mm
64ths	27/32″	0.84375	21.4313	+0.0953 mm

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

Common questions

What is 21/25 as a decimal?: 21/25 is exactly 0.84 as a decimal.
What is 21/25 as a percentage?: 21/25 is exactly 84%.
How many millimetres is 21/25 of an inch?: 21/25 of an inch is 21.336 mm, computed with the exact definition 1 inch = 25.4 mm.

0.84 as a fractionThe same number from the decimal's side, with the reduction shown.84% as a fractionThe same number as a percentage, with the work shown.Fraction–decimal chartThe everyday set, printable.Rule charts16ths, 32nds, 64ths, 128ths.The rulerSee 21/25 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.