R3CK0N

Powers of 2, from 2⁰ to 2³²

Powers of 2 turn up in computing (bytes, memory, colour depth), in doubling problems and in mental math shortcuts. Here is the full table, and the one fact that lets you rebuild it from memory.

The table

PowerValue
2⁰1
2¹2
2²4
2³8
2⁴16
2⁵32
2⁶64
2⁷128
2⁸256
2⁹512
2¹⁰1,024
2¹¹2,048
2¹²4,096
2¹³8,192
2¹⁴16,384
2¹⁵32,768
2¹⁶65,536
2¹⁷131,072
2¹⁸262,144
2¹⁹524,288
2²⁰1,048,576
2²¹2,097,152
2²²4,194,304
2²³8,388,608
2²⁴16,777,216
2²⁵33,554,432
2²⁶67,108,864
2²⁷134,217,728
2²⁸268,435,456
2²⁹536,870,912
2³⁰1,073,741,824
2³¹2,147,483,648
2³²4,294,967,296

The shortcut: 2¹⁰ ≈ 1,000

2¹⁰ is 1,024, just over a thousand. So every ten powers of 2 add roughly three zeros:

2¹⁰ = 1,024 ≈ 1 thousand 2²⁰ = 1,048,576 ≈ 1 million 2³⁰ = 1,073,741,824 ≈ 1 billion

To get any power, split the exponent into tens and a remainder. 2²³ = 2²⁰ × 2³ ≈ 1 million × 8 = 8 million (exactly 8,388,608). 2³² = 2³⁰ × 2² ≈ 4 billion (exactly 4,294,967,296).

The estimate always runs a little low, and the gap grows: it's 4.6% short at 2²⁰ and 6.9% short at 2³⁰.

Where you'll see them

Doubling in your head

Climbing the table is just repeated doubling, and doubling a big number is easiest left to right: 8,192 doubled is 16,000 + 384 = 16,384. If doubling and halving feel slow, the rest of mental math will too. R3CK0N's timed multiplication drill builds that speed.

Drill multiplication