Rules for writing units
Rule Description | Incorrect Format | Correct Format |
Separate the value and the unit with one space. | 3km | 3 km |
If the value is a fraction, separate numerator and denominator by a forward slash '/' symbol. | 3 by 5 km | 3/5 km |
For multiplying two or more units, put one space or asterisk '*' between them. | 5 J-s 5 J . s |
5 J s 5 J*s |
Separate numerator and denominator of the units using '/' or 'per' symbol. | 5 kmperhr | 5 km/hr 5 km per hr |
For adding dimensions to the unit, use the caret '^' symbol to add both positive and negative powers. | 5 kg / m(2) 5 kg / m**2 5 kg m^(-2) |
5 kg / m^2 5 kg / m^2 5 kg m^-2 |
In case of multiple units in the denominator, enclose them within the parenthesis. | 5 kg / m * s 5 kg/m*s |
5 kg / (m * s) 5 kg / m / s |
Write beginning units (like currencies) with or without a space. | 5 Rs 5$ 5 $ |
Rs 5 $5 $ 5 |
Allowable units
Base | Unit |
Length | meter (m), inch (in), foot (ft), yard (yd), mile (mi), link (li), rod (rd), chain (ch), angstrom, mil |
Surface area | m2, sqin, sqft, sqyd, sqmi, sqrd, sqch, sqmil, acre, hectare |
Volume | m3, litre (l, L, lt, liter), cc, cuin, cuft, cuyd, teaspoon, tablespoon |
Angles | rad (radian), deg (degree), grad (gradian), cycle, arcsec (arcsecond), arcmin (arcminute) |
Time | second (s, secs, seconds), minute (mins, minutes), hour (h, hr, hrs, hours), day (days), week (weeks), month (months), year (years), decade (decades), century (centuries), millennium (millennia) |
Frequency | hertz (Hz) |
Mass | kilogram (kg), gram (g), tonne, ton, grain (gr), dram (dr), ounce (oz), poundmass (lbm, lb, lbs), hundredweight (cwt), stick, stone |
Electric current | ampere (A) |
Temperature | kelvin (K), celsius (degC), fahrenheit (degF), rankine (degR) |
Amount of substance | mole (mol) |
Luminous intensity | candela (cd) |
Force | newton (N), dyne (dyn), poundforce (lbf), kip |
Energy | joule (J), erg, Wh, BTU, electronvolt (eV) |
Power | watt (W), horsepower (hp) |
Pressure | Pa, psi, atm, torr, bar, mmHg, mmH2O, cmH2O |
Electricity and magnetism | ampere (A), coulomb (C), watt (W), volt (V), ohm, farad (F), weber (Wb), tesla (T), henry (H), siemens (S), electronvolt (eV) |
Binary | bit (b), byte (B) |
Currency | $ (dollar(s), Dollar(s)), ₹ (Rs, Rupee(s), rupee(s)), Cent(s) / cent(s), Paisa / paise |