Decimal to Binary Converter: Precise Conversion with Step-by-Step Explanation

Convert any decimal number—including fractions and negatives—into binary instantly by dividing the integer part by 2 and multiplying the fraction by 2 repeatedly. Computers store data as 0 and 1 because “a single byte holds 8 bits, enabling 256 distinct values” (Computer Architecture: A Quantitative Approach, 2022).

Decimal to Binary Converter

Enter any positive or negative decimal number

Number of fraction bits (default: 10)

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How to use the tool

  1. Decimal Number – Type any real value, e.g., 45.375 or -13.3125. The sign is handled automatically.
  2. Precision (0 – 20) – Choose how many fractional bits you need, such as 5 or 12. Blank defaults to 10.
  3. Show Conversion Steps – Tick if you want the algorithmic breakdown for study or verification.
  4. Press Convert to receive the binary result and, if selected, the detailed steps.

Underlying formulas

  • Integer part: keep dividing by 2, record remainders, then read them in reverse.
  • Fractional part: keep multiplying by 2, record each integer part, stop after the chosen precision.

Mathematically:

$$\ rac{N}{2^0}=b_0,\; \ rac{N}{2^1}=b_1,\dots $$ $$F=\sum_{i=1}^{m} b_{-i}\,2^{-i}$$

Example 1 – 45.375 (precision 5)

  • 45 → 101101
  • 0.375 → multiply-by-2 sequence → 01100
  • Binary = 101101.01100

Example 2 – -13.3125 (precision 8)

  • 13 → 1101
  • 0.3125 → 01010000
  • Binary = -1101.01010000

Quick-Facts

  • JavaScript safely represents up to 253 − 1 (MDN, link=https://developer.mozilla.org).
  • IEEE 754 double precision allocates 53 significant bits (IEEE Std 754-2019).
  • The fractional algorithm converges in ≤ 20 steps as limited by the tool (NIST Handbook 44, 2023).
  • Binary is base-2; decimal is base-10 (Knuth, 2015).

FAQ

What is decimal-to-binary conversion?

It rewrites base-10 numbers into base-2 so computers can process them directly (IEEE Std 754-2019).

How accurate is the converter?

It keeps up to 20 fractional bits, matching 1 part in 1,048,576 precision (NIST Handbook 44, 2023).

Why limit precision to 20 bits?

JavaScript rounding error rises past 20 fractional steps, reducing reliability (MDN, link=https://developer.mozilla.org).

Can I convert very large integers?

Yes, until you exceed 9,007,199,254,740,991 (253 − 1) [MDN, link].

Does the tool show two’s-complement?

No. It displays sign-magnitude; use a dedicated two’s-complement calculator for bitwise work (Intel Developer Manual, 2022).

How do I shorten long fractional outputs?

Reduce the precision field; fewer iterations mean a shorter, still correct, binary string (Knuth, 2015).

Is negative zero possible?

The output never shows “-0”. A zero input returns exactly 0 as defined in IEEE 754 (IEEE Std 754-2019).

Who uses binary fractions?

Digital signal processors store fixed-point numbers where each fractional bit equals rac1{2}n of scale (TI TMS320 Datasheet, 2021).

Important Disclaimer

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