Type any arithmetic expression — with parentheses, exponents, ×÷, and +− — and evaluate it in correct PEMDAS / BODMAS order. The answer updates live, and every reduction step is shown so you can see exactly which operation happens when.
Type * or × for multiply, / or ÷ for divide, ^ for powers. Brackets [ ] and work too.
6 + 2 × 3 − (4 + 1) ^ 2
Updates live
The order of operations is the agreed-upon rule for which calculation to do first when an expression mixes several operations. Without it, 6 + 2 × 3 could mean either 24 or 12 — the rule guarantees everyone, and every calculator, lands on the same answer. It is summed up by the acronyms PEMDAS and BODMAS.
Work down the priority list one rank at a time, always resolving the left-most operation within the current rank before moving right.
Simplify everything inside brackets, working from the innermost pair outward. A bracketed group is its own little expression — finish it completely before using its value.
Evaluate any powers and roots — the exponent calculator shows the expansion. An exponent attaches only to the number directly beneath it unless brackets group more.
Handle × and ÷ next. They share a rank, so sweep left to right — do not save all the multiplying for last.
Finish with + and −, again left to right. Whatever is left is now a simple running total.
Each of these is a question people get wrong by reading left to right. Tab through to see the PEMDAS reductions the calculator performs.
Reading left to right gives 24. PEMDAS does the × first, so the answer is 12.
The single most misunderstood part of PEMDAS: the M does not always beat the D, and the A does not always beat the S. Equal-rank operations are taken in reading order.
Different countries teach the rule under different acronyms, which makes people think there are two systems. There is only one — the letters just rename the same priorities.
| Priority | PEMDAS (US) | BODMAS (UK) | Means |
|---|---|---|---|
| 1st | Parentheses | Brackets | ( ) [ ] { } |
| 2nd | Exponents | Orders | powers & roots |
| 3rd | Multiply / Divide | Divide / Multiply | × ÷ (left to right) |
| 4th | Add / Subtract | Add / Subtract | + − (left to right) |
Note the apparent flip in the third row — BODMAS lists Division before Multiplication — but because they share a rank and run left to right, the answer never changes.
This expression goes viral every few years because two reasonable readings of the same line give two different answers. The disagreement is about notation, not arithmetic.
The honest answer is that the expression is badly written. Adding one pair of brackets — (8 ÷ 2)(2 + 2) or 8 ÷ (2(2 + 2)) — removes all doubt. When in doubt, over-bracket.
Nearly every order-of-operations error comes from one of these. Knowing them is most of the battle.
Type symbols however you like — the calculator normalizes them. Powers use the caret, and any bracket style works.
| Operation | Type any of | Rank | Example |
|---|---|---|---|
| Group | ( ) [ ] { } | 1st | (2 + 3) × 4 = 20 |
| Power | ^ | 2nd | 2^3 = 8 |
| Multiply | × · * | 3rd | 4 × 5 = 20 |
| Divide | ÷ / | 3rd | 20 ÷ 4 = 5 |
| Add | + | 4th | 7 + 8 = 15 |
| Subtract | − - | 4th | 9 − 4 = 5 |
| Decimals | . | — | 3.5 × 2 = 7 |
| Negatives | − in front | — | −3 + 5 = 2 |
One shared convention so that a formula written by one person means the same thing to everyone — and every machine — that reads it.

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