Convert numbers to and from scientific notation. Handle very large and very small numbers with ease.
Scientific notation expresses numbers as: a × 10ⁿ
Scientific notation writes a number as a coefficient between 1 and 10 multiplied by a power of ten, for example 1.23456789 × 108 for 123,456,789. This converter finds the exponent by taking the base-10 logarithm of your number, then reports the scientific form, the e-notation shorthand (1.23456789e8), and the comma-grouped standard form side by side. In the reverse direction it multiplies your coefficient by 10 raised to the exponent you enter.
The notation exists because very large and very small quantities are unwieldy in ordinary digits. The speed of light, Avogadro's number, the mass of a proton, and Planck's constant, all available as one-click examples on this page, are far easier to compare and multiply in scientific form. Scientists, engineers, and programmers rely on it daily; calculators and programming languages switch to e-notation automatically when numbers get extreme, and the timestamp converter shows the same idea with Unix timestamps while the unit converter covers measurement conversions.
Two limitations are worth knowing. The coefficient is displayed to six significant digits, which matches the precision most estimates need, and the underlying arithmetic uses your browser's double-precision numbers, accurate to roughly 15 to 17 significant digits. For exponents beyond about plus or minus 20 in reverse mode, the tool keeps the answer in e-notation rather than printing a digit string longer than that precision supports.
A compact way to write very large or very small numbers as a coefficient times a power of ten: 6.022 × 10^23 instead of 602,200,000,000,000,000,000,000. The coefficient is at least 1 and less than 10, and the exponent counts how many places the decimal point moved. Extreme values become readable, comparable, and far easier to multiply and divide.
The e stands for exponent and is calculator and programming shorthand for 'times ten to the power of'. So 1.23e8 equals 1.23 × 10^8, or 123,000,000, and 1.6e-10 equals 0.00000000016. You will see it in spreadsheet output, in languages like Python and JavaScript, and on scientific calculators.
Move the decimal point until exactly one non-zero digit remains to its left, then count the moves. For 45,000 you shift 4 places left to get 4.5, so the result is 4.5 × 10^4. For 0.00032 you shift 4 places right, which gives a negative exponent: 3.2 × 10^-4.
That normalization guarantees every number has exactly one scientific notation. Without the rule, 4,500 could be written 4.5 × 10^3, 45 × 10^2, or 0.45 × 10^4. Locking the coefficient between 1 and 10 makes comparisons instant: the number with the larger exponent is the larger value.
Constantly in science and engineering: astronomical distances, molecular masses, electric charges, and probabilities all span dozens of orders of magnitude. It also appears in everyday computing whenever a value overflows normal display, such as large timestamps, financial models, or tiny error rates.