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Scientific Notation Calculator

Convert any number to scientific notation (a × 10^b) and back to plain decimal form, and read E-notation too — type a plain number or a scientific value.

Enter a plain number (e.g. 123000 or 0.00045) or scientific form (e.g. 6.02e23 or 4.5 x 10^-4). Everything converts instantly.

Scientific notation4.5 × 10^-4
E-notation4.5e-4
Standard (decimal) form0.00045
Coefficient a4.5
Exponent b-4

Scientific notation writes a number as a × 10b with 1 ≤ |a| < 10. The exponent b is how many places the decimal point moves: positive for large numbers, negative for small ones.

Quick answer

Scientific notation writes a number as a coefficient times a power of ten, a × 10^b, with 1 ≤ |a| < 10. So 0.00045 becomes 4.5 × 10^-4 and 123000 becomes 1.23 × 10^5. This converter accepts a plain number or a value like 6.02e23 and shows the scientific, E-notation, and standard forms.

Formula & method

The tool finds the exponent b = ⌊log10|n|⌋ and the coefficient a = n / 10^b, adjusting at boundary cases so 1 ≤ |a| < 10. It also parses input written as scientific or E-notation (e.g. '4.5 x 10^-4' or '6.02e23') and rebuilds the standard decimal form by shifting the decimal point b places.

Examples

Example 1: Small number
Input
0.00045
Result
4.5 × 10⁻⁴
Why
Move the decimal point 4 places right to reach 4.5, so the exponent is −4.
Example 2: Large number
Input
123000
Result
1.23 × 10⁵
Why
Move the decimal point 5 places left to reach 1.23, so the exponent is 5.
Example 3: From E-notation
Input
6.02e23
Result
602,000,000,000,000,000,000,000
Why
The standard form shifts the decimal 23 places right.

When to use this tool

  • Working with very large or very small quantities in science and engineering.
  • Reading or entering calculator and spreadsheet E-notation.
  • Comparing orders of magnitude quickly.

Common mistakes

  • Writing a coefficient outside the 1–10 range, such as 12 × 10^3 instead of 1.2 × 10^4.
  • Getting the exponent sign backwards — small numbers (< 1) have a negative exponent.
  • Losing significant figures when converting very large or very small numbers by hand.

Frequently asked questions

What is scientific notation?

A way of writing numbers as a × 10^b where the coefficient a satisfies 1 ≤ |a| < 10 and b is an integer exponent. It makes very large and very small numbers compact.

What is E-notation?

A plain-text form of scientific notation used by calculators and computers, where 'e' replaces '× 10^'. So 6.02 × 10^23 is written 6.02e23.

How do I find the exponent?

Count how many places you move the decimal point to get a coefficient between 1 and 10. Moving left gives a positive exponent; moving right gives a negative one.

Can I convert back to a normal number?

Yes. Enter the scientific or E-notation value and the tool shows the standard decimal form.

Why is 0.00045 written with a negative exponent?

Because it is less than 1. You move the decimal 4 places to the right to reach 4.5, which corresponds to 10^-4.

Does it keep precision?

It carries up to 12 significant digits and avoids floating-point noise in the displayed forms.

Sources & references

External references open in a new tab. We are independent and not affiliated with these organizations.

  • ✓ Free to use
  • ✓ No sign-up required
  • ✓ Runs entirely in your browser — nothing is uploaded.
  • ✓ Formula and method shown above
Last updated: How we calculateReport a correctionDisclaimer

Provided “as is” for general information only — results may be inaccurate, so verify before you rely on them. No warranty; use at your own risk.

Built and reviewed by HIFreeTools against the formula shown above and any authoritative references cited on this page. See our methodology and editorial standards.

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