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Engineering function

BIN2DEC

Converts a binary number to decimal.

Rarely usedDifficulty 1200 · ProficientUsage rank #335 of 520
Practice · 2 questions →

When to use it

Converts a binary number (up to 10 bits) to decimal. Ten bits with a leading 1 are read as negative two's complement.

The shape of it

Syntax
=BIN2DEC(number)

Worked examples

  • Small binary

    =BIN2DEC("1010") 10

    Ten.

  • Unquoted

    =BIN2DEC(101) 5

    A number typed without quotes works too.

  • Negative

    =BIN2DEC("1111111111") -1

    Ten ones is -1 in two's complement.

Worth knowing

  • DECIMAL(text,2) handles longer binary strings without the sign rule.
  • DEC2BIN reverses it.
  • Leading zeros are fine.

Where it goes wrong

  • #NUM! for more than 10 characters or a digit other than 0 or 1.
  • Values above 511 come back negative.

Related

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