Convert a number to scientific notation (a × 10ⁿ), expand it back to standard form, or do arithmetic in notation — with the coefficient, exponent, and every step shown live as you type.
Any decimal — large, small, or negative. Commas are ignored.
Scientific notation writes any number as a single significant digit before the decimal, times a power of ten. It separates the significant figures from the scale, so a number that would sprawl across the page becomes a tidy pair: a coefficient and an exponent.
Three steps turn any number into a × 10ⁿ.
Place the decimal point just after the first non-zero digit. That gives a coefficient between 1 and 10.
Count how many places the point travelled. Left moves give a positive exponent; right moves give a negative one.
Combine the two: the coefficient times ten raised to that exponent. Drop trailing zeros from the coefficient.
The same coefficient-and-exponent split makes multiplication, division, and even addition mechanical. Each tab computes its own working.
Four rules cover every operation. Multiply and divide act on the exponents directly; add and subtract need a shared exponent first.
Scientific notation is the working language of any field that deals with extreme scales.
Every common power of ten with its expanded value, everyday name, and SI prefix. Filter by exponent (try 6), by name (try million), or by prefix (try milli).
| Power | Value | Name | SI prefix |
|---|---|---|---|
| 10¹² | 1,000,000,000,000 | trillion | tera (T) |
| 10⁹ | 1,000,000,000 | billion | giga (G) |
| 10⁶ | 1,000,000 | million | mega (M) |
| 10³ | 1,000 | thousand | kilo (k) |
| 10² | 100 | hundred | hecto (h) |
| 10¹ | 10 | ten | deca (da) |
| 10⁰ | 1 | one | — |
| 10⁻¹ | 0.1 | tenth | deci (d) |
| 10⁻² | 0.01 | hundredth | centi (c) |
| 10⁻³ | 0.001 | thousandth | milli (m) |
| 10⁻⁶ | 0.000001 | millionth | micro (µ) |
| 10⁻⁹ | 0.000000001 | billionth | nano (n) |
| 10⁻¹² | 0.000000000001 | trillionth | pico (p) |
A few constants and everyday magnitudes, shown both ways — proof of how much notation compresses.
| Quantity | Scientific notation |
|---|---|
| Avogadro's number (particles per mole) | 6.022 × 10²³ |
| One light-year, in metres | 9.461 × 10¹⁵ |
| Earth–Sun distance, in metres | 1.496 × 10¹¹ |
| Human population (approx.) | 7.5 × 10⁹ |
| Speed of light, in m/s | 3 × 10⁸ |
| One millimetre, in metres | 1 × 10⁻³ |
| One micron (red-blood-cell scale), in metres | 1 × 10⁻⁶ |
| Bohr radius (atom scale), in metres | 5.29 × 10⁻¹¹ |
| Electron mass, in kilograms | 9.109 × 10⁻³¹ |
Most scientific-notation slips come from the same handful of habits. Watch for these.
One quiet advantage of notation: it makes precision unambiguous. The digits in the coefficient are the significant figures — no trailing-zero guesswork.

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