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Where can you find an allen wrench size chart?


Since allen wrenches are small and fairly cheap, you'll probably find that one has been included with any at-home assembly furniture. However, allen wrenches can be useful on other ways around the house, especially if you do a bit more than just put together the odd bookcase or two. In that case, you'll want a range of allen wrenches to make sure you have the right size for every particular need.

The good news is that just about every tool manufacturer has a range of allen wrench sets you can buy. You can find a chart of the allen wrench sizes from any manufacturer. The basic range of sizes (although not all sizes are included in all sets) is:

  • 0.7 millimeters
  • 0.9 millimeters
  • 1.2 millimeters (3/64 inch)
  • 1.3 millimeters
  • 1.5 millimeters
  • 1.6 millimeters (1/16 inch)
  • 2.0 millimeters (5/64 inch)
  • 2.4 millimeters (3/32 inch)
  • 2.5 millimeters
  • 2.8 millimeters (7/64 inch)
  • 3.0 millimeters
  • 3.2 millimeters (1/8 inch)
  • 3.5 millimeters (9/64 inch)
  • 4.0 millimeters (5/32 inch)
  • 4.4 millimeters (11/64 inch)
  • 4.5 millimeters
  • 4.8 millimeters (3/16 inch)
  • 5.0 millimeters
  • 5.2 millimeters (13/64 inch)
  • 5.5 millimeters (7/32 inch)
  • 6.0 millimeters (15/64 inch)
  • 6.4 millimeters (1/4 inch)
  • 7.0 millimeters
  • 8.0 millimeters (5/16 inch)
  • 9.0 millimeters
  • 9.5 millimeters (3/8 inch)
  • 10.0 millimeters
  • 12.7 millimeters (1/2 inch)

The smaller-sized allen wrenches need more maintenance than the larger ones. You can more easily strip the head on a small allen wrench if you're not careful. So be sure that the hex bolt is clean before you insert the allen wrench and that you've inserted it with all six sides properly aligned. Also, if you buy a cheaper set of allen wrenches, the small ones may not be so precise in their measurements, which means they won't work as well (or eventually at all) within their size bolts.


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