Nerdulator> put something in

Recognised as Decimal number

0.21

  • Positive
  • Decimal
  • 2 d.p.
  • Exact fraction
  • 2 s.f.

0.21 is a decimal number equal to 21⁄100. It lies between 0 and 1, and as a percentage it is 21%.

Number properties

Absolute value0.21
SignPositive
Integer part0
Fractional part0.21
Decimal places2
Floor0
Ceiling1
Rounded to nearest0
Truncated0

Fractions & ratios

As a fraction21/100exact
Ratio21 : 100
As a percentage21%
Reciprocal4.7619047619

Arithmetic

Double0.42
Half0.105
Square0.0441
Cube0.009261
Square root0.4582575695
Cube root0.5943921953
Negation-0.21
Natural logarithm-1.5606477483
Logarithm base 10-0.6777807053

Representations

Decimal0.21
Scientific notation2.1 × 10^-1
Exponential2.1e-1
IEEE 754 binary64 (hex)0x3FCAE147AE147AE1the exact 64-bit pattern stored
IEEE 754 binary32 (hex)0x3E570A3D32-bit single precision, may lose accuracy
Stored as0.21the nearest binary64 value to what you typed

Rounding & precision

Significant figures as written2counted from the digits as typed, not from the value
To 0 decimal places0
To 1 decimal place0.2
To 2 decimal places0.21
To 3 decimal places0.210
To 4 decimal places0.2100
To 1 significant figure0.2
To 2 significant figures0.21
To 3 significant figures0.210
To 4 significant figures0.2100

Keep nerding

Every link below is a page Nerdulator can generate from what it already knows about this value.

Neighbouring values

As a fraction

Also reads as

00:21 (time of day)

  • 00:21
  • 12:21 am
  • 1,260 s
  • 1.5% of the day

00:21 is 1,260 seconds after midnight, 1.4583% of the way through the day, with 23 hours and 39 minutes remaining. In twelve-hour form it is 12:21 am, and the hour and minute hands sit 115.5° apart.

Open this reading on its own page →

The time

24-hour00:21
12-hour12:21 am
Hours, minutes, seconds0 h 21 m 0 s
Seconds since midnight1,260
Minutes since midnight21
Decimal hours0.35the form payroll and timesheets use
Milliseconds since midnight1,260,000

Position in the day

Through the day1.458333%
Remaining until midnight85,140 seconds23 hours and 39 minutes
Elapsed21 minutes
Half of the day passedNobefore noon
Through the hour35%
Quarter of the day1six-hour quarters

Clock hands

Hour hand10.5° from twelvemoving continuously, so it sits between the hour marks
Minute hand126° from twelve
Second hand0° from twelve
Angle between hour and minute115.5°
Hands alignedNo

As a frame count

At 24 fps30,240film
At 25 fps31,500PAL
At 30 fps37,800
At 60 fps75,600
At 29.97 fps37,762.24NTSC is exactly 30000/1001 frames per second, not 29.97
Timecode at 25 fps00:21:00:00

Relative to now

These values depend on today’s date and change daily.

Now (UTC)12:00:51
Next occurrencein 12 hours, 20 minutes and 9 seconds
On today's date16 September 2026 at 00:21UTC; this page knows nothing of your timezone

Keep nerding

Every link below is a page Nerdulator can generate from what it already knows about this value.

Landmarks in the day

Nerdulate something else

Nothing in mind? Surprise me · today’s page

Every value on this page was computed from “0.21” by Nerdulator’s number engine. Nothing here was retrieved from a database of answers or written by a model.