[cstdint.syn]

namespace std { using int8_t = signed integer type; // optional using int16_t = signed integer type; // optional using int32_t = signed integer type; // optional using int64_t = signed integer type; // optional using int_fast8_t = signed integer type; using int_fast16_t = signed integer type; using int_fast32_t = signed integer type; using int_fast64_t = signed integer type; using int_least8_t = signed integer type; using int_least16_t = signed integer type; using int_least32_t = signed integer type; using int_least64_t = signed integer type; using intmax_t = signed integer type; using intptr_t = signed integer type; // optional using uint8_t = unsigned integer type; // optional using uint16_t = unsigned integer type; // optional using uint32_t = unsigned integer type; // optional using uint64_t = unsigned integer type; // optional using uint_fast8_t = unsigned integer type; using uint_fast16_t = unsigned integer type; using uint_fast32_t = unsigned integer type; using uint_fast64_t = unsigned integer type; using uint_least8_t = unsigned integer type; using uint_least16_t = unsigned integer type; using uint_least32_t = unsigned integer type; using uint_least64_t = unsigned integer type; using uintmax_t = unsigned integer type; using uintptr_t = unsigned integer type; // optional }

The header also defines numerous macros of the form:

  INT_[FAST LEAST]{8 16 32 64}_MIN
  [U]INT_[FAST LEAST]{8 16 32 64}_MAX
  INT{MAX PTR}_MIN
  [U]INT{MAX PTR}_MAX
  {PTRDIFF SIG_ATOMIC WCHAR WINT}{_MAX _MIN}
  SIZE_MAX

plus function macros of the form:

  [U]INT{8 16 32 64 MAX}_C

17 Language support library [support]

17.4 Integer types [cstdint]

17.4.2 Header <cstdint> synopsis [cstdint.syn]