Scientific notation converter
Convert between scientific, decimal, engineering notation and significant figures.
- Instant
- Free
- Private (processed locally)
- No sign-up
Every notation of a number, at once
Enter a number, decimal or scientific: the tool shows the scientific notation, the expanded decimal form, engineering notation, E-notation, the number of significant figures and an adjustable rounding.
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Enter the number
E.g. 12345 or 6.022e23.
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Set significant figures
For the rounding (1 to 12).
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Read every form
Scientific, decimal, engineering, E-notation.
Conversion examples
| Input | Scientific | Engineering | Sig. figures |
|---|---|---|---|
| 12345 | 1.2345 × 10⁴ | 12.345 × 10³ | 5 |
| 0.00042 | 4.2 × 10⁻⁴ | 420 × 10⁻⁶ | 2 |
| 6.022e23 | 6.022 × 10²³ | 602.2 × 10²¹ | 4 |
The expanded decimal form is built by string manipulation, with no display loss. Everything stays in your browser.
Frequently asked questions
What is scientific notation?
A compact way to write very large or very small numbers as a × 10ⁿ, where 1 ≤ a < 10. Example: 12345 is written 1.2345 × 10⁴ and 0.00042 is written 4.2 × 10⁻⁴.
How does engineering notation differ?
It forces an exponent that is a multiple of 3, aligned with prefixes (kilo, mega, micro…). 12345 becomes 12.345 × 10³ and 0.00042 becomes 420 × 10⁻⁶. Handy for electronics and SI units.
How do I count significant figures?
Count all digits from the first non-zero one. 12345 has 5 significant figures; 0.00042 has 2; 1200 without a decimal point has 2 (ambiguous zeros). The tool shows the detected count and lets you round.
Does the tool handle E-notation?
Yes: it reads inputs like 6.022e23 and shows the output in E-notation (6.022e+23), the form used by calculators and programming languages.