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Calculators/Maths/Arithmetic in standard form
Maths

Arithmetic in standard form calculator

Add, subtract, multiply or divide two numbers written as a × 10ⁿ.

Published 6 August 2026 · Updated 23 September 2026

What this calculator does

Standard form writes any number as a coefficient between 1 and 10 times a power of ten. Multiplying and dividing are easy in this form, since the exponents simply add or subtract, but adding requires matching the exponents first.

The difference shows in the arithmetic. Multiplying 5 × 10³ by 2 × 10² gives 1.000 × 10⁶ immediately, while adding them requires converting to the same power first and gives 5.200 × 10³.

The formula

Formula(a×10^m) op (b×10^n), renormalised so 1 ≤ |coefficient| < 10

Both numbers are expanded, the operation is applied, and the result is renormalised so the coefficient falls between 1 and 10.

TermMeaning
Standard formA coefficient between 1 and 10 multiplied by a power of ten.
RenormalisingAdjusting the coefficient and exponent so the coefficient is in range.
E-notationThe same thing written as 5.2e3, which calculators and computers use.

The inputs explained

FieldWhat to enter
Coefficient aCoefficient of the first number.
Exponent mExponent of the first number.
OperationWhich operation to perform.
Coefficient bCoefficient of the second number.
Exponent nExponent of the second number.

When to use it

Science calculations

Physical constants and measurements are almost always written in standard form.

Checking a calculator result

E-notation output is easy to misread by an order of magnitude.

Learning the rules

Multiplication and addition behave quite differently in this form.

Worked examples

Every figure in the tables below is produced by this page’s own calculator at build time, so the numbers and the tool always agree. Select any row to load that scenario.

How does each operation behave?

The same pair under all four operations.

5 × 10³ against 2 × 10²
OperationResult in standard formResult, unrounded
Add5.200 × 10^35,200
Subtract4.800 × 10^34,800
Multiply1.000 × 10^61,000,000
Divide2.500 × 10^125
Adding gives 5.200 × 10³ and subtracting 4.800 × 10³, both requiring the exponents to be matched first. Multiplying gives 1.000 × 10⁶, where the exponents simply added, and dividing gives 2.500 × 10¹.

Questions

Why is multiplication easier than addition?

Because exponents add under multiplication, so the two parts can be handled separately. Addition requires both numbers to share an exponent before the coefficients can be combined, which means converting one of them first.

Why must the coefficient be between 1 and 10?

So that every number has exactly one standard form. Without the constraint, 5,200 could be written as 5.2 × 10³, 52 × 10² or 0.52 × 10⁴, and comparisons would be needlessly awkward.

Is scientific notation the same thing?

Yes. Standard form is the British term and scientific notation the American one for the identical convention. Engineering notation differs slightly, restricting exponents to multiples of three.

What does e mean on a calculator?

It is shorthand for "times ten to the power of". A display of 5.2e3 means 5.2 × 10³, or 5,200. It has nothing to do with the mathematical constant e.

For general percentage work, see the percentage calculator. For significant figures in measurement, see the percent error calculator.