Binary to Gray code circuit: build and simulate it online

Gray code changes one bit at a time: G3 = B3, and each other bit is the XOR of neighbours.

Build the binary to gray code in the free online simulator — it checks your circuit automatically.

What you need

  • 4 logic switches labelled B3, B2, B1, B0
  • 4 probes labelled G3, G2, G1, G0
  • 3 XOR gates

Step by step

  1. Inputs and outputs. From the Logic section of the library, drop digital inputs (0/1 boxes) or logic switches for the inputs, and digital outputs or probes for the outputs; give each its label in the inspector (the checker finds them by label). Switches B3, B2, B1, B0; Probes G3, G2, G1, G0
  2. Three XOR gates. G2 = B3 ⊕ B2, G1 = B2 ⊕ B1, G0 = B1 ⊕ B0; G3 is just B3.
  3. Prove it. All 16 codes.

Truth table

B3B2B1B0G3G2G1G0
00000000
00010001
00100011
00110010
01000110
01010111
01100101
01110100
10001100
10011101
10101111
10111110
11001010
11011011
11101001
11111000

Frequently asked questions

How do you build a binary to gray code?

Gray code changes one bit at a time: G3 = B3, and each other bit is the XOR of neighbours. In short: inputs and outputs, then three xor gates, then prove it.

What is the truth table of a binary to gray code?

It has 4 inputs (B3, B2, B1, B0) and 4 outputs (G3, G2, G1, G0), so 16 rows. The full table is on this page; the Embedded Lab checks all of them against your circuit.

What parts do you need for a binary to gray code?

3 XOR gates — plus logic switches for the inputs and probes for the outputs.

Can I simulate a binary to gray code online for free?

Yes. Open it in the BitForBytes Embedded Lab, a free browser-based circuit and logic simulator: drag in the gates, wire them, and press "Check my circuit" — every input combination is simulated and marked for you. No download or sign-up needed.

Part of DSD 25 · Code converters in the free BitForBytes digital system design course.

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