1. What does this tool do
This free online scientific notation converter converts between decimal and scientific notation in one click—E-notation, engineering notation, or ×10ⁿ style. Use it for decimal to scientific notation or scientific to decimal in science, engineering, or programming. Enter a number in either form and get the equivalent; supports very large and very small numbers. No sign-up, no upload; all in your browser. Ideal for science, engineering, programming, education, or data analysis.
2. How to use it
Quick start: Choose "Decimal → Scientific" or "Scientific → Decimal", enter a number (or paste E-notation, ×10ⁿ, etc.), pick output format if needed, then view and copy the result.
- Select mode — Choose "Decimal → Scientific" to convert from decimal to exponential notation, or "Scientific → Decimal" for the reverse.
- Select output format (Decimal → Scientific only) — Choose E-notation, Engineering, ×10ⁿ (superscript), or ×10^n (caret).
- Enter input — Type a number. When converting to decimal, you can use any supported format: 1.23e+6, 1.23×10⁶, 1.23×10^6, or 123×10³.
- View output — The converted value appears instantly. Copy with one click.
- Sample or clear — Use Load sample to try an example, or Clear to reset.
3. How it works
Decimal to scientific: The input is normalized (alternative formats like ×10⁶ are converted to e-notation internally), parsed with parseFloat(), and validated. Output is formatted according to the selected format. Scientific to decimal: The input is normalized to handle ×10ⁿ, ×10^n, and engineering forms. For very small numbers the tool uses toFixed(20) and trims trailing zeros. Infinity and NaN are rejected. All computation runs entirely in your browser. No data is sent to any server.
4. Use cases & examples
- Science & engineering — Work with Avogadro's number, Planck's constant, or other physical constants. Use engineering notation for values with metric prefixes.
- Programming — Convert between user-friendly decimals and machine-readable e-notation for APIs or configs.
- Education — Teach or learn scientific notation, engineering notation, and significant figures.
- Data analysis — Normalize numeric strings from spreadsheets or CSV files.
- Publishing — Generate ×10ⁿ superscript form for papers and slides.
Examples
1230000→ 1.230000e+6 (E-notation)0.000123→ 1.230000e-41.23e-4→ 0.000123
5. Limitations & known constraints
- Number precision — JavaScript's Number type has about 15–17 significant digits. Very long decimal strings may lose precision.
- Input length — Maximum 500 characters to avoid performance issues.
- Infinity & NaN — Not supported; the tool rejects non-finite values.
- Very large numbers — Values with |n| ≥ 1e21 are displayed in e-notation even in "Scientific → Decimal" mode.
- Superscript display — Unicode superscript characters may render or copy differently across OS and applications.