Scientific Notation to Decimal Calculator
Convert scientific notation (mantissa and exponent) to a plain decimal and engineering notation.
How it works
x = m × 10ᵉ — shift the decimal point e places (right if e > 0, left if e < 0)
Scientific notation writes a number as a mantissa times a power of ten, m × 10ᵉ. Converting back to a plain decimal just shifts the decimal point e places — right for a positive exponent, left for a negative one. Engineering notation is the same idea locked to exponents that are multiples of three, so the powers line up with metric prefixes like kilo and milli.
Worked example
1.23 × 10⁵ moves the decimal point five places to the right, giving 123,000. In engineering notation, where the exponent must be a multiple of three, the same value is 123 × 10³.
Frequently asked questions
What do the mantissa and exponent mean?
The mantissa is the significant digits and the exponent is the power of ten. 1.23 × 10⁵ means take 1.23 and shift its decimal point five places to the right.
What is engineering notation?
A variant of scientific notation where the exponent is always a multiple of three, matching metric prefixes like kilo (10³) and micro (10⁻⁶). So 1.23 × 10⁵ becomes 123 × 10³.
Which way does the decimal point move?
A positive exponent moves it right, making the number larger; a negative exponent moves it left, making it smaller. The exponent is exactly how many places it shifts.
Related calculators
This calculator is for educational purposes. Double-check important results before acting on them.