Scientific Notation Converter
Enter a number in any form — standard, scientific (1.5 × 1010) or E notation (1.5e10) — and get all four forms back at once, exactly.
What Is a Scientific Notation Converter?
Scientific notation writes a number as a coefficient between 1 and 10 times a power of ten — a × 10n — so that enormous and tiny quantities become short enough to read, compare and type. The mass of the Earth is 5.97 × 1024 kg; the mass of an electron is 9.1 × 10−31 kg. Written out in full, those numbers are a 25-digit string and a decimal with 30 zeros — unusable. This converter takes a number in any of its common written forms and shows all of them side by side: standard decimal, scientific notation, E notation and engineering notation.
It works in both directions because the input box recognises the form you give it. Paste a plain number like 45000000, an E-notation value from a spreadsheet like 1.5e10, or a textbook form like 3.45 x 10^5, and every other form updates instantly. It also works on the digits themselves as text, not as floating-point numbers, so very long values convert with every digit exact — no silent rounding past 16 digits.
How to Convert to Scientific Notation — Step by Step
- Find the first non-zero digit of the number. That digit starts the coefficient.
- Place the decimal point immediately after it, and keep the remaining significant digits after the point: 45,000,000 → 4.5…
- Count how many places the decimal point moved from its original position. Moved left = positive exponent, moved right = negative: from the end of 45,000,000 to after the 4 is 7 places left, so the exponent is 7.
- Write it as coefficient × 10exponent: 4.5 × 107.
To go back, reverse the move: for 7.2 × 10−4, the exponent −4 says move the point 4 places left from 7.2, padding with zeros — 0.00072. Or just type either form into the box above and read the other off the results.
Worked Examples
| Standard form | Scientific notation | E notation | Engineering notation |
|---|---|---|---|
| 45,000,000 | 4.5 × 107 | 4.5e+7 | 45 × 106 |
| 12,345 | 1.2345 × 104 | 1.2345e+4 | 12.345 × 103 |
| 0.00045 | 4.5 × 10−4 | 4.5e-4 | 450 × 10−6 |
| 0.00072 | 7.2 × 10−4 | 7.2e-4 | 720 × 10−6 |
| 15,000,000,000 | 1.5 × 1010 | 1.5e+10 | 15 × 109 |
| 602,200,000,000,000,000,000,000 | 6.022 × 1023 | 6.022e+23 | 602.2 × 1021 |
| −2,500 | −2.5 × 103 | -2.5e+3 | −2.5 × 103 |
The last-but-one row is Avogadro's number, the count of particles in a mole — a figure almost never written in standard form, because the standard form is 24 characters of mostly zeros. Try typing 6.022e23 into the converter and watch the zeros come back.
The Four Forms, Compared
- Standard form is the ordinary written number — exact and unambiguous, but unreadable at extremes.
- Scientific notation (a × 10n, coefficient 1 to just under 10) is the classroom and journal standard; the exponent alone tells you the order of magnitude.
- E notation swaps × 10n for the letter e — 4.5e+7 — because code, calculators and spreadsheets need something typeable on one line.
- Engineering notation forces the exponent to a multiple of 3 so it matches SI prefixes (kilo 103, mega 106, milli 10−3, micro 10−6); the coefficient then runs from 1 to just under 1,000.
For the base conversions programmers live in, see the Binary Converter; for powers, roots and trigonometry, the Scientific Calculator.
Frequently Asked Questions
What is scientific notation?
Scientific notation is a way of writing very large or very small numbers compactly: a coefficient between 1 and 10 multiplied by a power of ten, written a × 10n. The distance to the Sun, about 150,000,000,000 metres, becomes 1.5 × 1011, and the mass of a dust particle can be written just as briefly with a negative power.
How do you convert a number to scientific notation?
Move the decimal point until exactly one non-zero digit sits to its left, then count how many places you moved — that count is the exponent. Moving left makes the exponent positive, moving right makes it negative. For 45,000,000 the point moves 7 places left, giving 4.5 × 107. For 0.00072 it moves 4 places right, giving 7.2 × 10−4.
How do you convert scientific notation back to a standard number?
Do the move in reverse: shift the coefficient's decimal point by the exponent — right for a positive exponent, left for a negative one — filling any gaps with zeros. So 7.2 × 10−4 becomes 0.00072 (point moved 4 places left), and 4.5 × 107 becomes 45,000,000 (7 places right). This converter accepts scientific notation as input and shows the full standard form.
What is E notation?
E notation is scientific notation written for computers and calculators, where 'e' replaces '× 10^'. The number 1.5 × 1010 is written 1.5e10 (or 1.5e+10), and 7.2 × 10−4 is 7.2e-4. Spreadsheets, code and CSV files use it because superscripts and multiplication signs are awkward to type and store.
What is engineering notation, and how is it different?
Engineering notation is scientific notation with one constraint: the exponent must be a multiple of 3, so the coefficient ranges from 1 up to (but not including) 1,000 instead of 1 to 10. That makes the exponent line up with SI prefixes — 103 is kilo, 106 is mega, 10−3 is milli, 10−6 is micro — so 45,000,000 is 45 × 106, read naturally as 45 mega.
What is 0 in scientific notation?
Zero is the special case: it is written 0 × 100 (0e0 in E notation). It has no first non-zero digit to anchor the coefficient, and multiplying by any power of ten still gives zero, so by convention the exponent is 0.
How do you write negative numbers in scientific notation?
The sign simply stays in front and the rest of the conversion is done on the absolute value: −2,500 becomes −2.5 × 103, and −0.00045 becomes −4.5 × 10−4. The coefficient itself is always written as a positive number between 1 and 10.
How exact is this converter for very long numbers?
Completely exact. The converter works on your digits as text rather than converting them into JavaScript's floating-point numbers, which silently round anything past about 16 digits. A 20-digit number like 12345678901234567890 converts to 1.234567890123456789 × 1019 with every digit intact, in both directions.
Is this scientific notation converter free to use?
Yes. It is completely free with no signup required, and it runs entirely in your browser — the numbers you enter are never uploaded or stored.