Convert numbers between binary, decimal, hex and octal

Options you can set

• Input base
• Base
• Also show base
• Group digits
• Uppercase letters (A-F)

Good to know

• Works with whole numbers of any size (up to 10,000 digits), including negative numbers. Fractions aren't supported.
• Spaces, underscores, commas and apostrophes inside a number are ignored, so 1_000_000 and 1,000,000 both work.
• Two's complement is shown for 8, 16, 32 and 64 bits whenever the number fits that width.
• Enter one number per line to convert several.

Number Base Converter FAQ

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