Decimal to binary converter

Enter a decimal number and get its binary value instantly, plus the other bases and the step-by-step working. Handles huge numbers, negatives and fractions.

digits 0–9
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Binarybase 20111 1110 1010
Octalbase 83752
Hexbase 167EA

Working for 202610

Divide by 2, keep the remainders

  1. DivisionQuotientRemainder
  2. 2026 ÷ 210130
  3. 1013 ÷ 25061
  4. 506 ÷ 22530
  5. 253 ÷ 21261
  6. 126 ÷ 2630
  7. 63 ÷ 2311
  8. 31 ÷ 2151
  9. 15 ÷ 271
  10. 7 ÷ 231
  11. 3 ÷ 211
  12. 1 ÷ 201

Read the remainders from the bottom up: 11111101010.

How to convert decimal to binary

  1. Divide the number by 2 and write down the remainder (0 or 1).
  2. Divide the quotient by 2 again, and repeat until the quotient is 0.
  3. Read the remainders from the last one to the first. 13 → 1, 0, 1, 1 read upward = 1101.

Decimal is the base people count in, so it is the usual starting or ending point when you need a value a human can check. Binary is how hardware stores everything: bit flags, network masks, file permissions and machine code are all patterns of 1s and 0s.

See place value move

Every bit is worth twice the bit to its right. Flip the switches and watch the decimal, hex and octal values rebuild.

32 + 8 + 4 + 1 = 45 · hex 2D · octal 55

Related conversions

Binary to decimal · Octal to binary · Decimal to octal · Decimal to hex · Hex to binary · any base 2–36 · signed (two's complement)

Questions people ask

How do you convert decimal to binary?

Divide the number by 2 and write down the remainder (0 or 1). Divide the quotient by 2 again, and repeat until the quotient is 0. Read the remainders from the last one to the first. 13 → 1, 0, 1, 1 read upward = 1101.

What is 2026 in binary?

2026 in decimal (base 10) is 11111101010 in binary (base 2).

Does it handle negative numbers and fractions?

Yes. A leading minus sign is kept, and digits after a point are converted too. Some fractions that end in one base repeat forever in another (0.1 in decimal is 0.000110011… in binary), so the result is cut at 24 digits and marked as repeating.

Is there a size limit?

No practical one. The converter uses arbitrary-precision integers (JavaScript BigInt), so 64-bit, 128-bit and longer values convert exactly, without rounding.