🔬 Scientific Notation Converter
299,792,458 = 2.99792458 × 10⁸, converted on the digits themselves, so a 21-digit number keeps all 21 digits instead of being rounded by floating point.
2.99792458 × 10⁸
scientific notation
2.99792458e8
e-notation
Conversion is done on the digits themselves, not via floating point, so 123456789012345678901 keeps every digit instead of becoming 1.2345678901234568e20. Runs locally.
How the scientific notation converter works
Both directions work on the digit string, not on a floating-point value. Number → scientific: find the first significant digit, place the decimal point after it, count how many places the point moved, that count is the exponent (positive for large numbers, negative for small ones like 0.00042 = 4.2 × 10⁻⁴). Scientific → number: shift the mantissa's decimal point by the exponent, padding zeros as needed. Because no float conversion ever happens, 123456789012345678901 converts exactly, a float-based tool would corrupt it to …78901 ≈ …79000 territory (doubles hold only ~15-17 significant digits). E-notation (2.998e8) is shown alongside, since that's what code and spreadsheets speak.
Scientific notation is really about significant figures: writing 2.99792458 × 10⁸ m/s asserts nine of them. When converting measured values, keep only the digits you actually know, the notation makes the claim visible. The ×10ⁿ form and e-notation are the same thing in different clothes; calculators and programming languages use e-notation because superscripts don't fit in ASCII.
Frequently asked questions
How do I convert a number to scientific notation?
Move the decimal point until exactly one non-zero digit is left of it; the number of places moved is the exponent, positive if the original number was ≥ 10, negative if it was < 1. 0.00042 → 4.2 × 10⁻⁴ (moved 4 right).
What is e-notation?
The plain-text form of scientific notation used by calculators and code: 2.998e8 means 2.998 × 10⁸, and 4.2e-4 means 4.2 × 10⁻⁴. The tool shows both.
Why "digit-exact", what goes wrong otherwise?
Converting via floating point limits you to ~15-17 significant digits: 123456789012345678901 silently becomes 123456789012345677312. This tool moves the decimal point in the digit string itself, so every digit survives.
What about significant figures?
Scientific notation displays them explicitly, 2.99792458 × 10⁸ claims nine. This converter preserves exactly the digits you type (trailing zeros after the point included in the mantissa you enter); deciding how many to keep is a judgment about your measurement, not the converter's.
Does it run locally?
Yes, pure string arithmetic in your browser, offline-capable.