One field, both directions. Type 602000000000000000000000 and get 6.02 × 10²³; type 6.02e23 and get the digits back. The engineering form and a significant-figure count come with it.
Key terms
- Scientific notation — one digit before the decimal point, times a power of ten. Also called standard form.
- Engineering notation — the same idea with the exponent restricted to multiples of three, so it lines up with kilo, mega, milli and micro.
- Significant figures — the digits that carry actual information about precision.
How it works
Standard form
m × 10ⁿ, where 1 ≤ |m| < 10 and n is a whole number
n is how many places the decimal point moves: positive to the right for large numbers, negative to the left for small ones.
The conversion is done on the digits, not on a number
A JavaScript number holds about 17 significant digits. Push a 30-digit value through one and it is silently rounded — and the rounded version then gets displayed as though it were what you typed.
So this converter moves the decimal point through the digit string directly. No arithmetic is involved, and the result is exact at any size. The one exception is rounding to a chosen number of significant figures, which does use arithmetic; past about 17 digits that step is rounding the stored value rather than your digits.
Trailing zeros in a whole number are ambiguous
How many significant figures does 1500 have? It could be two, three or four. The digits alone cannot tell you whether those zeros were measured or are just holding the place.
This is exactly the ambiguity scientific notation was invented to remove. Written 1.5 × 10³ it has two significant figures. Written 1.500 × 10³ it has four. There is no way to say either thing with the digits 1500 alone, so this page reports the smaller, defensible count and explains that the larger one cannot be claimed.
After a decimal point the rule flips: those zeros are significant. 0.00450 has three significant figures, because the final zero was written deliberately. Dropping it would claim less precision than the measurement had.
Engineering notation is not the same thing
Engineering notation keeps the exponent to multiples of three, so 47000 is written 47 × 10³ rather than 4.7 × 10⁴. The point is that every exponent maps to an SI prefix — 10³ is kilo, 10⁶ is mega, 10⁻³ is milli, 10⁻⁶ is micro. That is why datasheets and electronics use it: 47 × 10³ Ω reads directly as 47 kΩ.
How to use this calculator
- Type your number in any form — plain digits, 6.02e23, or 6.02 × 10^23.
- Read the scientific and engineering forms, and the count of significant figures.
- Set the significant-figures box to round the value for a report or an answer sheet.
- If the note mentions ambiguity, rewrite the number in scientific notation to state your precision explicitly.
Frequently asked questions
What is scientific notation used for?
Writing very large and very small numbers without long runs of zeros, and stating precision unambiguously. It also makes magnitudes easy to compare — 10²³ against 10²¹ is instantly a factor of a hundred.
Is standard form the same as scientific notation?
Yes. “Standard form” is the usual British name and “scientific notation” the American one; the rule — one digit before the point, times a power of ten — is identical.
What does the e mean in 6.02e23?
It is shorthand for “times ten to the power of”, used because keyboards and calculator displays have no superscript. 6.02e23 and 6.02 × 10²³ are the same number.
How many significant figures does 0.00450 have?
Three. Leading zeros only place the decimal point and never count, but the trailing zero after the point does, because it was written on purpose to show precision.
Why does my calculator show 6.02E+23?
It has run out of display width and switched to exponential notation automatically. It is the same value written more compactly; type it into the field above to see the digits in full.
