SI Prefixes Used with Units

Below are shown the prefixes (factors) used with units of lengths, mass, area, volume, etc. The symbol, the name, and the corresponding factor are presented in the table below. Examples with each of the 12 symbols are also included. More exercises with solutions are presented at the bottom of the page.

Note: Several forms of the factors corresponding to the SI prefixes are given: decimal, division, fraction, and power to cater to all levels. In the examples below, the calculations are done using the decimal form, however the other forms may also be used.

Definition of Prefixes

A prefix (in units) is a word that precedes a basic unit, such as meter, grams, etc., that indicates a multiple (\( > 1 \)) or fraction (\( < 1 \)) of the basic unit.

For example, kilometer is made of the prefix kilo (in Greek) which means a thousand and the basic unit meter.

1 kilometer = 1000 meters

The table below shows the names of some of the mostly used prefixes, their abbreviations, and the corresponding factor.

Metric SI Prefixes Table
Table 1 - Metric SI Prefixes

Examples with Solutions

Basic units such as meter (length), liter (volume), gram (mass), and Watt (power) are used in the examples below.

Example 1

Convert \( 7 \; \color{red}{\textbf{pico}}\textbf{meters} \) to meters.

Example 2

Convert \( 3.2 \; \color{red}{\textbf{nano}}\textbf{meters} \) to meters.

Example 3

Convert \( 8 \; \color{red}{\textbf{micro}}\textbf{grams} \) to grams.

Example 4

Convert \( 0.4 \; \color{red}{\textbf{milli}}\textbf{liters} \) to liters.

Example 5

Convert \( 7 \; \color{red}{\textbf{centi}}\textbf{grams} \) to grams.

Example 6

Convert \( 2.01 \; \color{red}{\textbf{deci}}\textbf{meters} \) to meters.

Example 7

Convert \( 5 \; \color{red}{\textbf{deka}}\textbf{meters} \) to meters.

Example 8

Convert \( 9.23 \; \color{red}{\textbf{hecto}}\textbf{liters} \) to liters.

Example 9

Convert \( 3.4 \; \color{red}{\textbf{kilo}}\textbf{grams} \) to grams.

Example 10

Convert \( 7.6 \; \color{red}{\textbf{Mega}}\textbf{Watts} \) to Watts.

Example 11

Convert \( 0.3 \; \color{red}{\textbf{Giga}}\textbf{Watts} \) to Watts.

Example 12

Convert \( 1.3 \; \color{red}{\textbf{Tera}}\textbf{Watts} \) to Watts.

Exercises

Part A

Identify the prefix used and convert to meters (m).

  1. \( 0.02 \text{ Mm} \)
  2. \( 234 \text{ dam} \)
  3. \( 1200 \text{ pm} \)
  4. \( 205 \text{ nm} \)
  5. \( 0.002 \text{ cm} \)
  6. \( 1.002 \text{ hm} \)
  7. \( 0.005 \text{ Gm} \)
  8. \( 1.34 \; \mu\text{m} \)
  9. \( 23000 \; \text{mm} \)
  10. \( 1.003 \; \text{dm} \)
  11. \( 0.02 \; \text{km} \)
  12. \( 0.01 \text{ Tm} \)

Part B

Identify the prefix used and convert to grams (g).

  1. \( 0.003 \text{ Tg} \)
  2. \( 0.3 \; \text{dg} \)
  3. \( 1.2 \; \text{kg} \)
  4. \( 1000 \; \mu\text{g} \)
  5. \( 0.056 \text{ Mg} \)
  6. \( 2.3 \text{ dag} \)
  7. \( 102.4 \text{ cg} \)
  8. \( 20.2 \text{ hg} \)
  9. \( 0.001 \text{ Gg} \)
  10. \( 1100 \text{ pg} \)
  11. \( 9000 \text{ ng} \)
  12. \( 23000 \; \text{mg} \)

Part C

Identify the prefix used and convert to liters (L).

  1. \( 200 \; \text{mL} \)
  2. \( 0.005 \text{ TL} \)
  3. \( 1.4 \text{ hL} \)
  4. \( 0.00002 \text{ GL} \)
  5. \( 440000 \text{ pL} \)
  6. \( 500 \text{ nL} \)
  7. \( 0.007 \text{ ML} \)
  8. \( 1.06 \text{ daL} \)
  9. \( 203.6 \text{ cL} \)
  10. \( 0.02 \; \text{dL} \)
  11. \( 10.1 \; \text{kL} \)
  12. \( 100 \; \mu\text{L} \)

More References and Links

  1. Convert Units of Measurements
  2. Factor of Conversion of Units
  3. Units Conversion and Calculators