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IEEE 754 Converter
Turn a decimal number into its 32-bit or 64-bit IEEE 754 bit pattern, or decode a hex pattern back to a value.
IEEE 754 float bits
Bit layout: —
Check: —
Sign: —
Exponent bits: —
Mantissa bits: —
Exponent bias: —
Unbiased exponent: —
Stored value: —
How to use the IEEE 754 Converter
- Choose single or double precision and the input type.
- Enter a decimal number or a hex bit pattern.
- Read the sign, exponent and mantissa fields with the decoded value.
Features
- 32-bit single and 64-bit double precision
- Sign, exponent and mantissa fields broken out
- Decode a hex bit pattern back to a decimal value
- Special values named: zero, infinity, NaN, subnormal
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Frequently Asked Questions
Common questions about the free online ieee 754 converter.
It is the standard way computers store floating point numbers as a sign bit, a biased
exponent and a fraction field.
Single precision uses 32 bits with 8 exponent bits and 23 fraction bits, while double
precision uses 64 bits with 11 and 52.
The stored exponent is shifted by 127 for single and 1023 for double, so the field can hold
negative exponents.
When the exponent field is all zeros but the fraction is not, the number is subnormal with a
much smaller magnitude.
An exponent field that is all ones with a zero fraction is infinity, and the sign bit decides
whether it is positive or negative.
An all ones exponent with a non zero fraction is not a number, which is how NaN is encoded.
Yes. Switch the input to a bit pattern, paste the hex digits and the decimal value is decoded
for you.
One tenth has no finite binary expansion, so the stored value is the nearest representable
float and differs slightly.
Yes. A sign bit of one with every other bit zero is reported as negative zero.
No. The conversion runs entirely in your browser with no upload and no logging.
Last updated: October 10, 2026