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Engineering function

DEC2BIN

Converts a decimal number to binary.

Rarely usedDifficulty 1200 · ProficientUsage rank #338 of 520
Practice · 2 questions →

When to use it

Converts a decimal number (-512 to 511) to binary text, optionally padded with zeros.

The shape of it

Syntax
=DEC2BIN(number, [places])

Worked examples

  • Simple

    =DEC2BIN(10) 1010

    Ten in binary.

  • Padded

    =DEC2BIN(5,8) 00000101

    Padded to eight bits.

  • Negative

    =DEC2BIN(-1) 1111111111

    Negatives are ten-bit two's complement.

Worth knowing

  • BASE(number,2,places) handles numbers beyond 511.
  • Bit flags: DEC2BIN(flags,8) shows which options are on.
  • The result is text.

Where it goes wrong

  • #NUM! outside -512 to 511 or when places is too small.
  • Non-integers are truncated.

Related

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