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Scientific Notation Converter – Standard Form, E and Engineering Notation

Convert any number into scientific notation (standard form), E notation and engineering notation — or turn scientific notation back into an ordinary decimal. Choose how many significant figures you want and get every format at once.

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How to use the scientific notation converter

  1. Type a number — an ordinary decimal like 0.000123 or 6022000000, or scientific notation like 4.5e-4 or 3.2 × 10^5.
  2. Set how many significant figures to keep.

You’ll see the number in scientific notation, E notation, engineering notation and as a plain decimal.

How to convert by hand

Large number: 123,000

  1. Place the decimal point after the first digit: 1.23
  2. You moved it 5 places to the left
  3. 1.23 × 10⁵

Small number: 0.000123

  1. Move the decimal point to just after the first non-zero digit: 1.23
  2. You moved it 4 places to the right
  3. 1.23 × 10⁻⁴ — in engineering notation 123 × 10⁻⁶

Back to a decimal: 4.5 × 10⁻³

Move the decimal point 3 places to the left: 0.0045.

Scientific notation: a × 10ⁿ, where 1 ≤ |a| < 10

Examples from science

QuantityDecimalScientific notation
Speed of light299,792,458 m/s2.998 × 10⁸ m/s
Avogadro’s number602,214,076,000,000,000,000,0006.022 × 10²³
Earth–Sun distance149,600,000 km1.496 × 10⁸ km
Width of a human hair0.00007 m7 × 10⁻⁵ m
Mass of an electron0.000…000911 kg9.11 × 10⁻³¹ kg

Engineering notation and SI prefixes

Engineering notation uses powers of 10 that are multiples of 3 so that they match the metric prefixes:

PowerPrefixExample
10⁹giga (G)2.4 GHz
10⁶mega (M)12 MP camera
10³kilo (k)5 km
10⁻³milli (m)250 mg
10⁻⁶micro (µ)10 µm
10⁻⁹nano (n)450 nm

Calculating with scientific notation

  • Multiply: multiply the numbers and add the powers. (2 × 10³) × (3 × 10⁴) = 6 × 10⁷.
  • Divide: divide the numbers and subtract the powers. (8 × 10⁶) ÷ (2 × 10²) = 4 × 10⁴.
  • Add or subtract: first rewrite so both have the same power of 10.

Calculators and spreadsheets

Most calculators switch to scientific notation when a number has too many digits to fit on the screen, and spreadsheets do the same with E notation: a cell showing 1.23E+12 holds 1,230,000,000,000. Programming languages accept the same format, so 6.02e23 can be typed directly into code. If a spreadsheet turns a long ID number such as a phone or card number into E notation, format the column as text before pasting so no digits are lost.

Spreadsheets also let you choose a “Scientific” number format to display values this way on purpose.

Significant figures

Scientific notation makes significant figures obvious: 1.20 × 10³ has three, 1.2 × 10³ has two. Use the significant figures calculator to count and round them, the exponent calculator for powers, or the scientific calculator for full expressions.

Frequently asked questions

What is scientific notation?

A way of writing a number as a value between 1 and 10 multiplied by a power of 10. 123,000 becomes 1.23 × 10⁵ and 0.000123 becomes 1.23 × 10⁻⁴. In the UK it is often called standard form.

How do I convert a number to scientific notation?

Move the decimal point until there is one non-zero digit in front of it. Count how many places you moved it: that is the power of 10 — positive if you moved left, negative if you moved right.

What is E notation?

A text-friendly version used by calculators, spreadsheets and programming languages: 1.23e5 means 1.23 × 10⁵ and 1.23e-4 means 1.23 × 10⁻⁴.

What is engineering notation?

Like scientific notation, but the power of 10 is always a multiple of 3, so it matches unit prefixes: 0.000123 becomes 123 × 10⁻⁶, which is 123 micro-units.

How do I type a number in scientific notation?

Any of these work: 6.02e23, 6.02E23, 6.02 × 10^23 or 6.02x10^23.

Why use scientific notation?

It makes very large and very small numbers easy to read, compare and calculate with, and it shows the significant figures clearly.

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