AND gate truth table
The AND gate outputs 1 only when both inputs are 1, and 0 otherwise. Here is its full truth table, the boolean expression, and how it is actually built.
| A | B | Y |
|---|---|---|
| 0 | 0 | 0 |
| 0 | 1 | 0 |
| 1 | 0 | 0 |
| 1 | 1 | 1 |
Boolean expression: Y = A · B. A 1 in the table means a high voltage (logic true) and a 0 means low (false). Read each row as: for these inputs, the output Y is this value.
What the AND gate does
AND is logical multiplication: the output is the product of the inputs, so it is 1 only when every input is 1. In CMOS it is built as a NAND gate followed by an inverter, because the natural pull-down network gives you the inverted form for free.
Build it yourself
Reading a table is one thing; watching the signals flow is another. Open the logic gate simulator and wire a AND gate up from transistors, or read the full lesson on how this gate is designed. You can also generate the table for any expression with the truth table generator.
Other gates:
The AND gate is one small step toward a working CPU. Build every gate from CMOS transistors and work up to an 8-bit processor in the free digiwleea lab and course.
Open the gate simulator →Frequently asked
What is the truth table of a AND gate?
The AND gate outputs 1 only when both inputs are 1, and 0 otherwise. For inputs (A,B) the outputs are 0,0→0 0,1→0 1,0→0 1,1→1.
What is the boolean expression for AND?
The AND gate is written Y = A AND B (symbolically Y = A · B).
How many transistors does a AND gate take?
A standard CMOS AND gate uses about 6 transistors. In digiwleea you build it from those transistors and the simulator verifies it against this exact truth table.