About the Scientific Notation Calculator
Very large and very small numbers are easier to handle in scientific notation, written as a number between 1 and 10 times a power of ten. This calculator does arithmetic directly in that form. Type two numbers as 3.2 x 10^5, 3.2e5 or even as ordinary numbers, choose add, subtract, multiply or divide, and it gives the answer in proper scientific notation with the steps a teacher would want to see. You can round to a chosen number of significant figures and copy the answer in E notation for spreadsheets and code.
Updated October 2026
How to use the Scientific Notation Calculator
- 1Type the first number, for example 3.2 x 10^5 or 3.2e5.
- 2Pick the operation.
- 3Type the second number.
- 4Choose whether to round to significant figures.
- 5Read the answer and the numbered steps.
Why scientific notation helps
Writing the distance to the Sun as 1.496 × 10¹¹ m or the mass of an electron as 9.109 × 10⁻³¹ kg keeps the important digits visible and the size obvious from the power. Arithmetic is easier too: multiplying and dividing only needs the front numbers and a sum of the powers.
The rules in short
Each rule ends by normalising the answer so one digit sits before the point.
- Multiply: multiply the front numbers, add the powers
- Divide: divide the front numbers, subtract the powers
- Add or subtract: match the powers first, then add or subtract the front numbers
- Normalise: move the point and change the power to keep 1 ≤ front number < 10
Worked example with steps
Multiply 3.2 × 10⁵ by 4.5 × 10⁻². The front numbers give 3.2 × 4.5 = 14.4 and the powers give 5 + (−2) = 3, so the raw answer is 14.4 × 10³. Moving the point one place left and adding one to the power gives 1.44 × 10⁴, which is 14,400 as an ordinary number.
Significant figures and E notation
Choose a rounding option to match your data. The E notation row, such as 1.44e4, is the form spreadsheets, programming languages and most calculators accept, so you can paste the answer straight in. Very large or tiny answers are not shown as ordinary numbers because they would be dozens of digits long.
Homework and lab work
The steps are written in plain words, so you can check your own working line by line. On a phone the numbered steps sit under the answer; on a computer they appear beside the inputs. Very large and very small numbers are easier with a few helpers. Use the Scientific Notation Converter to change forms, the Significant Figures Counter to check precision, and the Exponent Calculator for powers.
Features
- All four operations
- Reads 3.2 x 10^5, 3.2e5 and plain numbers
- Step-by-step working
- Rounding to 2–6 significant figures
- E notation and ordinary number shown
- Handles powers far beyond a normal calculator
Frequently asked questions
How do you multiply numbers in scientific notation?
Multiply the numbers in front and add the powers of ten, then tidy up. (3 × 10⁴) × (5 × 10⁶) = 15 × 10¹⁰ = 1.5 × 10¹¹.
How do you divide numbers in scientific notation?
Divide the numbers in front and subtract the powers. (6 × 10⁸) ÷ (2 × 10³) = 3 × 10⁵.
How do you add numbers in scientific notation?
Rewrite them with the same power of ten first. 2.5 × 10³ + 4 × 10² = 2.5 × 10³ + 0.4 × 10³ = 2.9 × 10³.
How do I type a power of ten?
Use x 10^5, × 10^5, *10^5 or e5. Negative powers work too: 4.5e-2 or 4.5 x 10^-2.
What does normalised mean?
A number in proper scientific notation has exactly one non-zero digit before the decimal point, such as 1.5 × 10¹¹ rather than 15 × 10¹⁰. The calculator always tidies the answer this way.
Why round to significant figures?
In science the answer shouldn't look more precise than the measurements. If your inputs have three significant figures, round the answer to three as well.