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Hex Calculator

Hex Signed Integer Calculator

Read a hex value as a signed integer type (int8, int16, int32, int64) — the same interpretation debuggers use when they show a variable's value.

Signed integer value
-1
Bit width

Full breakdown (input at 8-bit)

Hexadecimal
0xFF
Decimal (unsigned)
255
Binary
11111111
Octal
377
Signed (8-bit)
-1
Set / clear bits
8 set, 0 clear

How Signed Integer Types Read Hex Bytes

A signed integer type doesn't change the bits in memory — it changes how they're interpreted. Pick the bit width matching the type (8, 16, 32, or 64), and the calculator checks the sign bit at that width: if it's set, the value is negative under two's complement; otherwise it reads as its plain positive value.

Signed Integer Type Ranges

TypeBit widthRange
int88-bit-128 to 127
int1616-bit-32,768 to 32,767
int3232-bit-2,147,483,648 to 2,147,483,647
int6464-bit-9,223,372,036,854,775,808 to 9,223,372,036,854,775,807

Common Mistakes Reading Signed Integer Hex

  • Picking the wrong bit width for the variable's actual declared type.
  • Assuming a hex byte is always positive without checking the sign bit.
  • Mixing up a signed type's range with its unsigned counterpart's range.

Frequently Asked Questions

What does it mean to read a hex value as a signed integer?

It means interpreting the bit pattern using two's complement at a specific integer type's width — int8 (8-bit), int16, int32, or int64 — so the same bits can represent either a positive or negative number depending on the sign bit.

Why do debuggers show the same hex bytes as different numbers?

Because the variable's declared type determines both the bit width and whether it's signed — an int8 and a uint8 holding the identical bit pattern 0xFF display as -1 and 255 respectively.

What's the range of each signed integer type?

int8 is -128 to 127, int16 is -32,768 to 32,767, int32 is about -2.1 billion to 2.1 billion, and int64 covers an enormous range — each type's negative range is one wider than its positive range.

How is this different from just reading a hex value as decimal?

Plain hex-to-decimal always gives a non-negative number. This calculator additionally checks the sign bit for the chosen integer width and returns a negative result when that bit is set — matching how signed variables actually behave in code.

Which integer type should I pick if I'm not sure?

Match it to the variable's declared type in your code or the field width in your data format — int8/int16/int32/int64 in most C-family languages, or check your language's documentation if the naming differs.

Is this the same as the Hex to Negative Decimal converter?

The underlying math is identical — this page frames it around programming integer types (int8/int16/int32/int64) specifically, for anyone debugging typed variables rather than doing general arithmetic.