Scientific Notation Converter — All Number Formats
Convert any number to scientific notation, engineering notation, E-notation, and SI prefix form simultaneously. Choose significant figures and copy each result with one click. Runs in your browser.
Enter a number above to see all notation formats.
How the Scientific Notation Converter Works
- 1Enter any number in the input — decimal, E-notation (1.5e8), or ×10^ format (1.5×10^8).
- 2Select your preferred significant figures (2–6).
- 3All five formats appear instantly: decimal, scientific, engineering, E-notation, and SI prefix.
- 4Click Copy next to any row to copy that notation to the clipboard.
When to Use Each Notation
Use scientific notation in physics and chemistry papers when exact precision matters. Use engineering notation in electronics and electrical engineering, where values align with component ratings (k ohm, mF, MHz). Use E-notation in code and spreadsheets. Use SI prefixes for everyday measurements and instrument readings.
Scientific Notation Tips
Speed of light: 3 × 10⁸ m/s
Try entering 299792458 — it converts to 2.998 × 10⁸ in scientific notation. The 3 × 10⁸ approximation is accurate to 1 sig fig and is the standard physics shorthand.
Avogadro's number: 6.022 × 10²³
Enter 6.022e23. This is the number of molecules in one mole of a substance, used constantly in chemistry. It is also a good test for very large number inputs.
Planck's constant: 6.626 × 10⁻³⁴ J·s
Enter 6.626e-34 — the quantum of action used in E=hf calculations. Very small numbers like this are where scientific notation is indispensable for clarity.
Match precision to your source
If your given value has 3 significant figures (e.g. 9.81 m/s²), set sig figs to 3. Reporting more sig figs than the measurement contains implies false precision.
Frequently Asked Questions
What is the difference between scientific and engineering notation?
Scientific notation uses any integer exponent (e.g. 1.23 × 10⁷). Engineering notation restricts the exponent to multiples of 3 (3, 6, 9, -3, -6…) so that coefficients align with SI prefixes like kilo, mega, and milli.
What is E-notation?
E-notation (or computer scientific notation) writes the exponent after the letter "e": 1.23e7 means 1.23 × 10⁷. It is used in programming languages and spreadsheets where superscripts are not available.
What are SI prefixes?
SI prefixes are standardised multiplier names for powers of 1000: kilo (k) = 10³, mega (M) = 10⁶, giga (G) = 10⁹, milli (m) = 10⁻³, micro (μ) = 10⁻⁶, nano (n) = 10⁻⁹, etc.
What input formats are accepted?
The converter accepts standard decimal (12345.67), E-notation (1.2e4), and the × 10^ format (1.2×10^4). Spaces are ignored. Negative numbers are also supported.
What does significant figures mean?
Significant figures (sig figs) are the meaningful digits in a number. The converter lets you choose 2–6 sig figs to control the precision of the output without changing the magnitude.
Why does the SI prefix output show a multiplier?
For numbers outside the standard SI prefix range (10⁻¹⁸ to 10²⁴), or for numbers exactly at base 10⁰, the output shows the raw multiplier instead of a prefix letter since no standard SI prefix applies.