Scientific Notation Converter
Enter a number to see it in scientific notation, E notation, engineering notation and as a plain number, with no rounding.
Four ways to write a number
- Scientific notation: the form a × 10ⁿ, where the absolute value of a is at least 1 and less than 10. A negative number keeps its minus sign on a. Example: 123000 = 1.23 × 10⁵.
- E notation: the same number written with E in place of "× 10" (used in calculators and programming). Examples: 1.23E5 and 1.23E-4.
- Engineering notation: the exponent is chosen to be a multiple of 3, so the absolute value of the mantissa is at least 1 and less than 1000 (it matches SI prefixes). Examples: 123000 = 123 × 10³ and 0.000123 = 123 × 10⁻⁶.
- Plain number (place value): the ordinary way of writing the number with zeros. It is omitted when it would be longer than 100 characters.
No rounding, and no guessing of significant figures
This converter only rewrites the decimal digits and never rounds them. There is no option to reduce the number of digits.
How trailing zeros are treated (a rule to avoid guessing significant figures):
- A number with a decimal point keeps the digits as written, including trailing zeros.
1.2300e3→ 1.2300 × 10³,0.0120→ 1.20 × 10⁻²,1200.→ 1.200 × 10³. - A whole number without a decimal point loses its trailing zeros.
1200→ 1.2 × 10³. A whole number such as 1200 does not show whether it has 2 or 4 significant figures, so its trailing zeros are not treated as significant. To keep them, enter1.200e3or1200.. - Leading zeros are removed (the leading zeros of
0.0120are not counted as digits). - Zero (
0,0.000and-0) is 0 × 10⁰ (−0 becomes 0).
This rule is a choice made by this converter, not a rule from a standard.
Examples
| Input | Scientific notation | E notation | Engineering notation |
|---|---|---|---|
| 123000 | 1.23 × 10⁵ | 1.23E5 | 123 × 10³ |
| 0.000123 | 1.23 × 10⁻⁴ | 1.23E-4 | 123 × 10⁻⁶ |
| -45.6 | -4.56 × 10¹ | -4.56E1 | -45.6 × 10⁰ |
| 1200 | 1.2 × 10³ | 1.2E3 | 1.2 × 10³ |
| 1.2300e3 | 1.2300 × 10³ | 1.2300E3 | 1.2300 × 10³ |
| 0.0120 | 1.20 × 10⁻² | 1.20E-2 | 12.0 × 10⁻³ |
| 1.23×10^5 | 1.23 × 10⁵ | 1.23E5 | 123 × 10³ |
Limits
- The mantissa can have up to 100 digits, and the exponent can be from −1000 to 1000 (both for the input and for the result). Beyond that, the reason is shown.
- Commas are accepted only as thousands separators in the integer part (1,234,567 or 1,234.5). Spaces and underscores are ignored. The decimal separator is a period.
- Full-width digits and symbols are converted to the normal characters.
Notes
- To convert between number bases (binary, octal, decimal and hexadecimal), use the Number Base Converter. For powers and logarithms, use the Exponent & Logarithm Calculator.
- This tool only rewrites how a number is written. It does not calculate with numbers.
Frequently asked questions
How do I write 123000 in scientific notation?
1.23 × 10⁵ (1.23E5 in E notation).
What is engineering notation?
A way of writing where the exponent is a multiple of 3. 123000 is written 123 × 10³. It matches the SI prefixes (k, M, m and so on).
Why does 1200 become 1.2 × 10³?
The trailing zeros of a whole number without a decimal point may or may not be significant, so they are removed. To keep them, enter 1.200e3 or 1200..
Does it round the number?
No. The digits are rewritten exactly as entered.