Scientific Notation Converter

Free scientific notation converter. Convert a decimal number to scientific notation (a × 10^n) and back, with mantissa, exponent, and standard e-notation output.

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How scientific notation converter works

Scientific notation expresses a number as a mantissa times a power of ten, in the form a × 10^n where the mantissa a has exactly one non-zero digit before the decimal point and the exponent n is an integer. It is the standard way to write very large or very small numbers compactly in science and engineering.

To convert a decimal to scientific notation, find the exponent that puts the decimal point after the first non-zero digit and divide the number by that power of ten. For 1234 the exponent is 3 and the mantissa is 1.234, giving 1.234 × 10^3. For 0.0056 the exponent is -3 and the mantissa is 5.6, giving 5.6 × 10^-3. Zero is a special case with exponent 0.

Enter a value and pick a direction. "To" converts a decimal into scientific notation and also gives the e-notation form (like 1.234e3). "From" converts a scientific-notation string like 1.23e4 back into a plain decimal. Use it for homework, physics and chemistry calculations, and translating between calculator displays and written work.

Frequently asked questions

What is scientific notation?
A number written as a × 10^n, where 1 ≤ |a| < 10 and n is an integer. For example 1234 = 1.234 × 10^3 and 0.0056 = 5.6 × 10^-3. It compactly expresses very large or small values.
How is the exponent found?
It is the power of ten needed to move the decimal point to just after the first non-zero digit. Moving the decimal left gives a positive exponent; moving it right gives a negative one.
What is e-notation?
A compact form used by calculators and programming languages, like 1.234e3 for 1.234 × 10^3. This converter gives both the written form (with × 10^n) and the e-notation form.
How is zero handled?
Zero has no unique scientific notation, so this converter returns "0" with exponent 0 rather than forcing a mantissa in the usual 1-to-10 range.