Scientific Notation Calculator
Work out scientific notation step by step: turn a plain number into a × 10ⁿ or expand it back, with engineering and E notation shown for each result.
How to use it
- Use the first tab to turn a plain number into scientific notation.
- Use the second tab to expand a mantissa and exponent back into a normal number.
- Engineering notation restricts the exponent to multiples of three, matching SI prefixes.
Examples
| 0.000345 | 3.45 × 10⁻⁴ |
| 6.022 × 10²³ | 602,200,000,000,000,000,000,000 |
Scientific notation writes a number as a small figure between 1 and 10 multiplied by a power of ten — a × 10ⁿ — so extremely large or small values (Avogadro's number, the mass of an electron, national debt figures) stay readable and easy to compare at a glance instead of trailing off in a wall of zeros.
Converting each direction
To go plain-to-scientific, move the decimal point until one non-zero digit sits before it, and count how many places it moved — that count is the exponent, negative if the point moved right (small numbers), positive if it moved left (large numbers). 0.000345 becomes 3.45 × 10⁻⁴, since the point moved 4 places right.
To go scientific-to-plain, do the reverse: move the decimal point n places, padding with zeros as needed. 6.022 × 10²³ becomes a 1 followed by the digits shifted 23 places — the number of atoms in a mole of carbon-12.
Scientific vs engineering notation
| Form | Exponent rule | Example (0.0000456) |
|---|---|---|
| Scientific | Mantissa between 1 and 10 | 4.56 × 10⁻⁵ |
| Engineering | Exponent restricted to multiples of 3 | 45.6 × 10⁻⁶ (45.6 micro-) |
Questions people ask
What is the difference between scientific and engineering notation?
Scientific notation keeps the mantissa between 1 and 10. Engineering notation uses exponents that are multiples of three, so the result lines up with kilo, mega, milli and micro.
Is anything sent to a server?
No. Every calculation runs in your browser, so nothing you type is uploaded and the page keeps working offline once it has loaded.
Last updated 17 August 2026