NAND is universal circuit: build and simulate it online
NOT, AND and OR — using nothing but NAND gates.
Build the nand is universal in the free online simulator — it checks your circuit automatically.
What you need
- 2 logic switches labelled A, B
- 3 probes labelled NOTA, AND, OR
- 3 NAND gates
- 5 or more NAND gates
Step by step
- 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 A, B; Probes NOTA, AND, OR
- NOT and AND from NAND. A NAND with both inputs tied is a NOT; a NAND followed by that NOT is an AND. NOT A: 1 NAND; A AND B: 2 NANDs
- OR from NAND. De Morgan: A + B = NOT(NOT A · NOT B): invert each input, then NAND. 3 more NANDs (6 in all)
- Prove it. The checker also makes sure no other kind of gate was used.
Truth table
| A | B | NOTA | AND | OR |
|---|---|---|---|---|
| 0 | 0 | 1 | 0 | 0 |
| 0 | 1 | 1 | 0 | 1 |
| 1 | 0 | 0 | 0 | 1 |
| 1 | 1 | 0 | 1 | 1 |
Frequently asked questions
How do you build a nand is universal?
NOT, AND and OR — using nothing but NAND gates. In short: inputs and outputs, then not and and from nand, then or from nand, then prove it.
What is the truth table of a nand is universal?
It has 2 inputs (A, B) and 3 outputs (NOTA, AND, OR), so 4 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 nand is universal?
3 NAND gates; 5 or more NAND gates — plus logic switches for the inputs and probes for the outputs.
Can I simulate a nand is universal 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 26 · Universal gates in the free BitForBytes digital system design course.