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FP32

abbreviationAlso: single precision, float32, binary32, float, TF32

In plain wordsThe standard 32-bit way computers store numbers with fractional parts, keeping about seven significant digits. It was the default for training AI until faster, smaller formats took over.

  1. The IEEE 754 single-precision floating-point formatfloating-point format, n.: A way of storing numbers in a computer like scientific notation — a few digits plus a power of two — trading accuracy for range. AI uses ever-smaller formats to compute faster. (binary32): 1 sign bit, 8 exponent bits and 23 stored significand bits, giving about 7 decimal digits of precision and a range up to about 3.4 × 10^38. It was the standard format for neural-network training until the late 2010s and remains the usual format for master weights, optimizer states, accumulations, loss computation and numerically sensitive operations in mixed-precision trainingmixed-precision training, n.: Training a model with shorter, less exact numbers for most of the arithmetic and full-length numbers only where accuracy really matters, which saves a great deal of memory and lets modern chips train far faster., while matrix arithmetic moves to bfloat16bfloat16, n.: A 16-bit number format invented at Google for AI. It keeps the huge range of the standard 32-bit format but drops precision, which neural networks can usually tolerate., FP8FP8, abbr.: An 8-bit number format that uses a quarter of the memory of the standard 32-bit format, letting new AI chips train and run models roughly twice as fast as with 16 bits. or narrower formats. TF32, introduced with Nvidia's A100 (2020), is a tensor-core mode that takes FP32 inputs but multiplies them with only 10 significand bits — FP32's range with FP16FP16, abbr.: A 16-bit way of storing numbers that uses half the memory of the standard 32-bit format. It is fast for AI but can't represent very large or very tiny values.'s precision — and accumulates in FP32.

Origin

Single precision was defined in IEEE 754-1985, standardizing earlier vendor formats; 'FP32' became the usual abbreviation in GPU and deep-learning writing in the 2010s.

Usage note

In deep-learning usage, 'full precision' usually means FP32, not FP64.

Related

See also
  • floating-point formatfloating-point format, n.: A way of storing numbers in a computer like scientific notation — a few digits plus a power of two — trading accuracy for range. AI uses ever-smaller formats to compute faster.
  • FP16FP16, abbr.: A 16-bit way of storing numbers that uses half the memory of the standard 32-bit format. It is fast for AI but can't represent very large or very tiny values.
  • bfloat16bfloat16, n.: A 16-bit number format invented at Google for AI. It keeps the huge range of the standard 32-bit format but drops precision, which neural networks can usually tolerate.
  • mixed-precision trainingmixed-precision training, n.: Training a model with shorter, less exact numbers for most of the arithmetic and full-length numbers only where accuracy really matters, which saves a great deal of memory and lets modern chips train far faster.
  • tensor coretensor core, n.: A small, specialized part of an AI chip that does one job — multiplying small blocks of numbers together — far faster than ordinary circuits can.
Contrast with
  • bfloat16bfloat16, n.: A 16-bit number format invented at Google for AI. It keeps the huge range of the standard 32-bit format but drops precision, which neural networks can usually tolerate.

Mentioned in

bfloat16bfloat16, n.: A 16-bit number format invented at Google for AI. It keeps the huge range of the standard 32-bit format but drops precision, which neural networks can usually tolerate., floating-point formatfloating-point format, n.: A way of storing numbers in a computer like scientific notation — a few digits plus a power of two — trading accuracy for range. AI uses ever-smaller formats to compute faster., FP16FP16, abbr.: A 16-bit way of storing numbers that uses half the memory of the standard 32-bit format. It is fast for AI but can't represent very large or very tiny values., mixed-precision trainingmixed-precision training, n.: Training a model with shorter, less exact numbers for most of the arithmetic and full-length numbers only where accuracy really matters, which saves a great deal of memory and lets modern chips train far faster., tensor coretensor core, n.: A small, specialized part of an AI chip that does one job — multiplying small blocks of numbers together — far faster than ordinary circuits can., Huang's lawHuang's law, n.: A claim, named after Nvidia's chief executive, that AI chip performance improves much faster than Moore's law because chips, software and number formats all improve together.