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millimeter
Symbol:  mm 
Category:  Length 
SI Equivalent:  1×10-3 m
Dimension:  L 
System:  SI 
Convert     mm  
5.21 mm =
Length
  Symbol Unit Name
9.84547×107  a.u., a0, b  a.u. of length 
5.21×107  Å  angstrom 
17.9107  arcmin  arcmin 
3.48267×10-14  AU, UA  astronomical unit 
5.21×1015  am  attometer 
0.615354    barleycorn (UK) 
9.84547×107  a0, b  bohr (first Bohr radius) 
1.42443×10-4    bolt (US cloth) 
2.46142  line (UK)  button (UK) 
8.20472  line (US)  button (US) 
2.81318×10-5    cable length (int.) 
2.81138×10-5    cable length (UK) 
2.37405×10-5    cable length (US) 
20.5118  caliber, cin  caliber (centiinch) 
0.521  cm  centimeter 
1.70932×10-4  ch  chain (engineer's) 
2.58988×10-4  ch  chain (Gunter's) 
1.70932×10-4  ch  chain (Ramsden's) 
2.58988×10-4  ch  chain (surveyor's) 
1.13955×10-2    cubit (UK) 
5.21×10-4  dam  decameter 
5.21×10-2  dm  decimeter 
1.84887×1012  re  electron classical radius 
4.55818×10-3    ell 
1.23533    ems (pica) 
5.21×10-21  Em  exameter 
2.84886×10-3  fath  fathom 
5.21×1012  fm  femtometer 
5.21×1012  F, f  fermi 
9.84547×107  a0, b, a.u.  first Bohr radius 
1.70932×10-2  ft  foot 
15.63  fr  French 
2.58988×10-5  fur  furlong (UK) 
2.58988×10-5  fur  furlong (US) 
5.21×10-12  Gm  gigameter 
5.12795×10-2  hd  hand (UK) 
5.21×10-5  hm  hectometer 
5.50709×10-28    hubble 
0.205118  in  inch 
5.21×10-6  km  kilometer 
1.68845×10-22  kpc  kiloparsec 
1.07935×10-6    league (Canadian) 
9.37725×10-7  leag. (int. naut.)  league (int. naut.) 
1.07911×10-6  leag. (stat.)  league (statute, land) 
9.37126×10-7  leag. (UK, naut.)  league (UK, naut.) 
9.37126×10-7  leag. (US, naut.)  league (US, naut.) 
2.01142×10-16    light-day 
4.82741×10-15    light-hour 
2.89645×10-13    light-minute 
1.73787×10-11    light-second 
5.50709×10-19  ly  light-year 
2.46142  line (UK)  line (UK) 
8.20472  line (US)  line (US) 
1.70932×10-2    link (engineer's) 
2.58988×10-2    link (Gunter's) 
1.70932×10-2    link (Ramsden's) 
2.58988×10-2    link (surveyor's) 
5.21×10-9  Mm  megameter 
5.21×10-3  m  meter 
2.05118×105  µin  microinch 
5210  µm  micron 
205.118  mil, thou  mil (thou) 
7.02006×10-7  mile (geogr.)  mile (geographical) 
3.23734×10-6  mi (int.)  mile (international) 
2.81318×10-6  mi (naut., int.)  mile (nautical, international) 
2.80814×10-6  mi (naut., teleg.)  mile (nautical, telegraph) 
2.81138×10-6  mi (naut., UK, US)  mile (nautical, UK, US) 
3.23734×10-6  mi (stat.)  mile (statute, land) 
3.23734×10-6  mi (survey, US)  mile (survey, US) 
5.21×106  mµ, nm  millimicron 
2.27909×10-2    nail (UK) 
5.21×106  nm  nanometer 
2.81318×10-6  mi (int. naut.)  nautical mile (international) 
2.81138×10-6  mi (UK, US, naut.)  nautical mile (UK, US) 
6.83727×10-3    pace (UK) 
6.83727×10-2    palm (UK) 
1.68845×10-19  pc  parsec 
1.03595×10-3  rd  perch (rod, pole) 
5.21×10-18  Pm  petameter 
1.23532    pica 
5.21×109  pm  picometer 
14.8239    point (US printer's) 
1.03595×10-3  rd  pole (rod, perch) 
5.21×10-10    quadrant 
1.03595×10-3  rd  rod (perch, pole) 
8.54659×10-4    rope (UK) 
2.27909×10-2    span 
5.21×10-15  Tm  terameter 
205.118  thou, mil  thou (mil) 
5.20892×1010  UX, X  X-unit 
5.69773×10-3  yd  yard 
5.21×1021  ym  yoctometer 
5.21×10-27  Ym  yottameter 
5.21×1018  zm  zeptometer 
5.21×10-24  Zm  zettameter 
Glossary
FREE Publications
Negotiate Your Salary

Learn the best principles to negotiate the salary you deserve!

Injection Molding Design Guide

Guide for high quality and cost-effective plastic injection molding.

3D Scanners

A white paper to assist in the evaluation of 3D scanning hardware solutions.

Metal 3D Printing Design Guide

Direct Metal Laser Sintering (DMLS) 3D printing for parts with reduced cost and little waste.

more publications