LABORATORY TOOLKIT
Tools, converters & reference tables for chemists
A curated set of practical utilities instant unit conversion, mesh-to-micron lookup, ppm/ppb relationships, common metric factors and a complete atomic weights index.
Featured tool
Universal Unit Converter
Convert between SI and imperial units across length, mass, volume, pressure, energy and temperature. Results update live as you type.
Length
Mass
Volume & Capacity
Pressure & Stress
Energy
Temperature
Live Converter
Need a different conversion? Browse the reference tables below.
Reference library
Conversion Tables & Atomic Data
Field-tested references compiled by our chemists for everyday lab use.
Particle size mesh to micron conversion
A " + " before a mesh size means particles are retained (larger than the sieve opening). A " − " means particles pass through (smaller than the opening). Example: −325 mesh means particles pass through and are smaller than 44 microns.
| Mesh | Microns | Millimeters | Inches |
|---|---|---|---|
| 4 | 4750 | 4.75 | 0.187 |
| 6 | 3350 | 3.35 | 0.132 |
| 8 | 2360 | 2.36 | 0.0937 |
| 12 | 1700 | 1.7 | 0.0661 |
| 16 | 1180 | 1.18 | 0.0469 |
| 20 | 850 | 0.85 | 0.0331 |
| 30 | 600 | 0.6 | 0.0234 |
| 40 | 425 | 0.425 | 0.0165 |
| 50 | 300 | 0.3 | 0.0117 |
| 60 | 250 | 0.25 | 0.0098 |
| 70 | 212 | 0.212 | 0.0083 |
| 80 | 180 | 0.18 | 0.007 |
| 100 | 150 | 0.15 | 0.0059 |
| 120 | 125 | 0.125 | 0.0049 |
| 140 | 106 | 0.106 | 0.0041 |
| 200 | 75 | 0.075 | 0.0029 |
| 230 | 63 | 0.063 | 0.0025 |
| 270 | 53 | 0.053 | 0.0021 |
| 325 | 45 | 0.045 | 0.0017 |
| 400 | 38 | 0.038 | 0.0015 |
Most common conversion factors
Quick equivalences between parts per million, parts per billion and percentage.
10,000 ppm
10,000,000 ppb
1.0%
1,000 ppm
1,000,000 ppb
0.1%
100 ppm
100,000 ppb
0.01%
10 ppm
10,000 ppb
0.001%
1 ppm
1,000 ppb
0.0001%
0.1 ppm
100 ppb
0.00001%
0.01 ppm
10 ppb
0.000001%
Length
| From | To | Multiply by |
|---|---|---|
| Inch | Centimeter | 2.54 |
| Foot | Centimeter | 30.48 |
| Yard | Meter | 0.9144 |
| Mile | Kilometer | 1.6093 |
Area
| From | To | Multiply by |
|---|---|---|
| Square inch | Square cm | 6.4516 |
| Square foot | Square meter | 0.092903 |
| Square yard | Square meter | 0.83613 |
Volume
| From | To | Multiply by |
|---|---|---|
| Cubic inch | Cubic centimeter | 16.387 |
| Cubic foot | Liter | 28.317 |
Mass
| From | To | Multiply by |
|---|---|---|
| Grain | Milligram | 64.799 |
| Dram | Gram | 1.7718 |
| Ounce | Kilogram | 0.028349 |
| Pound | Kilogram | 0.45359 |
Pressure
| From | To | Multiply by |
|---|---|---|
| Inch of H2O | Pascal | 249.09 |
| Inch of Mercury | Pascal | 3386.4 |
Energy & Power
| From | To | Multiply by |
|---|---|---|
| BTU | Joule | 1055.1 |
| Horsepower | Joule/second | 745.7 |
Atomic weights
Based on atomic mass C = 12.
H
Hydrogen
Atomic weight
1.008
He
Helium
Atomic weight
4.0026
Li
Lithium
Atomic weight
6.94
Be
Beryllium
Atomic weight
9.0122
B
Boron
Atomic weight
10.811
C
Carbon
Atomic weight
12.011
N
Nitrogen
Atomic weight
14.007
O
Oxygen
Atomic weight
15.999
F
Fluorine
Atomic weight
18.9984
Ne
Neon
Atomic weight
20.1797
Na
Sodium
Atomic weight
22.9898
Mg
Magnesium
Atomic weight
24.305
Al
Aluminum
Atomic weight
26.9815
Si
Silicon
Atomic weight
28.0855
P
Phosphorus
Atomic weight
30.9738
S
Sulfur
Atomic weight
32.065
Cl
Chlorine
Atomic weight
35.4527
Ar
Argon
Atomic weight
39.948
K
Potassium
Atomic weight
39.0983
Ca
Calcium
Atomic weight
40.078
Sc
Scandium
Atomic weight
44.9559
Ti
Titanium
Atomic weight
47.867
V
Vanadium
Atomic weight
50.9415
Cr
Chromium
Atomic weight
51.9961
Mn
Manganese
Atomic weight
54.938
Fe
Iron
Atomic weight
55.845
Co
Cobalt
Atomic weight
58.9332
Ni
Nickel
Atomic weight
58.6934
Cu
Copper
Atomic weight
63.546
Zn
Zinc
Atomic weight
65.38
Ga
Gallium
Atomic weight
69.723
Ge
Germanium
Atomic weight
72.63
As
Arsenic
Atomic weight
74.9216
Se
Selenium
Atomic weight
78.971
Br
Bromine
Atomic weight
79.904
Kr
Krypton
Atomic weight
83.798
Rb
Rubidium
Atomic weight
85.4678
Sr
Strontium
Atomic weight
87.62
Y
Yttrium
Atomic weight
88.9058
Zr
Zirconium
Atomic weight
91.224
Nb
Niobium
Atomic weight
92.9064
Mo
Molybdenum
Atomic weight
95.95
Tc
Technetium
Atomic weight
98
Ru
Ruthenium
Atomic weight
101.07
Rh
Rhodium
Atomic weight
102.9055
Pd
Palladium
Atomic weight
106.42
Ag
Silver
Atomic weight
107.8682
Cd
Cadmium
Atomic weight
112.411
In
Indium
Atomic weight
114.818
Sn
Tin
Atomic weight
118.710
Sb
Antimony
Atomic weight
121.75
Te
Tellurium
Atomic weight
127.60
I
Iodine
Atomic weight
126.9045
Xe
Xenon
Atomic weight
131.293
Cs
Cesium
Atomic weight
132.9054
Ba
Barium
Atomic weight
137.327
La
Lanthanum
Atomic weight
138.9055
Ce
Cerium
Atomic weight
140.115
Pr
Praseodymium
Atomic weight
140.9077
Nd
Neodymium
Atomic weight
144.242
Pm
Promethium
Atomic weight
145
Sm
Samarium
Atomic weight
150.36
Eu
Europium
Atomic weight
151.96
Gd
Gadolinium
Atomic weight
157.25
Tb
Terbium
Atomic weight
158.9254
Dy
Dysprosium
Atomic weight
162.50
Ho
Holmium
Atomic weight
164.9303
Er
Erbium
Atomic weight
167.26
Tm
Thulium
Atomic weight
168.9342
Yb
Ytterbium
Atomic weight
173.045
Lu
Lutetium
Atomic weight
174.9668
Hf
Hafnium
Atomic weight
178.49
Ta
Tantalum
Atomic weight
180.9479
W
Tungsten
Atomic weight
183.84
Re
Rhenium
Atomic weight
186.207
Os
Osmium
Atomic weight
190.23
Ir
Iridium
Atomic weight
192.217
Pt
Platinum
Atomic weight
195.084
Au
Gold
Atomic weight
196.9666
Hg
Mercury
Atomic weight
200.592
Tl
Thallium
Atomic weight
204.38
Pb
Lead
Atomic weight
207.2
Bi
Bismuth
Atomic weight
208.9804
Po
Polonium
Atomic weight
209
At
Astatine
Atomic weight
209.9871
Rn
Radon
Atomic weight
222
Fr
Francium
Atomic weight
223.0197
Ra
Radium
Atomic weight
226.0254
Ac
Actinium
Atomic weight
227.0278
Th
Thorium
Atomic weight
232.0381
Pa
Protactinium
Atomic weight
231.0359
U
Uranium
Atomic weight
238.0289
Np
Neptunium
Atomic weight
237.0482
Pu
Plutonium
Atomic weight
244.0642
Am
Americium
Atomic weight
243.0614
Cm
Curium
Atomic weight
247.0703
Bk
Berkelium
Atomic weight
247.0703
Cf
Californium
Atomic weight
251.0796
Es
Einsteinium
Atomic weight
252.0829
Fm
Fermium
Atomic weight
257.0951
Md
Mendelevium
Atomic weight
258.0984
No
Nobelium
Atomic weight
259.101
Lr
Lawrencium
Atomic weight
266
Rf
Rutherfordium
Atomic weight
267
Db
Dubnium
Atomic weight
268
Sg
Seaborgium
Atomic weight
269
Bh
Bohrium
Atomic weight
270
Hs
Hassium
Atomic weight
269
Mt
Meitnerium
Atomic weight
278
Ds
Darmstadtium
Atomic weight
281
Rg
Roentgenium
Atomic weight
282
Cn
Copernicium
Atomic weight
285
Nh
Nihonium
Atomic weight
286
Fl
Flerovium
Atomic weight
289
Mc
Moscovium
Atomic weight
290
Lv
Livermorium
Atomic weight
293
Ts
Tennessine
Atomic weight
294
Og
Oganesson
Atomic weight
294