Screw Size Identifiers
Inch
Metric
Find thread size, screw size, diameter, or drill bit size.
| For Use With | For Thread Type | For Thread Location | For Thread Size  | For Screw Size | For Dia. | For Drill Bit Size | Wd. | Ht. | Thick. | Each | |
Inch | |||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|
Steel | |||||||||||
| Screws, Bolts, Threaded Rods, Pins, Rivets, Drill Bits | UNC/UNF | External | 1-64, 1-72, 2-56, 2-64, 3-48, 3-56, 4-36, 4-40, 4-48, 5-40, 5-44, 6-32, 6-36, 6-40, 8-32, 8-36, 8-40, 10-24, 10-32, 12-24, 12-28, 12-32, 1/4"-20, 1/4"-28, 1/4"-32, 5/16"-18, 5/16"-24, 5/16"-32 | No. 1, No. 2, No. 3, No. 4, No. 5, 1/8", No. 6, 5/32", No. 8, 3/16", No. 10, No. 12, 7/32", 1/4", 9/32", 5/16" | 0.073", 0.086", 3/32", 0.112", 1/8", 0.138", 5/32", 0.164", 3/16", 7/32", 1/4", 9/32", 5/16" | 7/32", 1/4", 9/32", 5/16", 53 ga, 51 ga, 50 ga, 48 ga, 47 ga, 45 ga, 43 ga, 42 ga, 39 ga, 38 ga, 37 ga, 36 ga, 35 ga, 33 ga, 30 ga, 29 ga, 28 ga, 25 ga, 23 ga, 21 ga, 19 ga, 16 ga, 14 ga, 13 ga, 10 ga, 8 ga, 3 ga, F, I | 3" | 5 1/8" | 5/64" | 000000000 | 000000 |
Metric | |||||||||||
Steel | |||||||||||
| Screws, Bolts, Threaded Rods | Metric | External | M8 × 0.75 mm, M8 × 1 mm, M8 × 1.25 mm, M9 × 0.75 mm, M9 × 1 mm, M9 × 1.25 mm, M10 × 0.75 mm, M10 × 1 mm, M10 × 1.25 mm, M10 × 1.5 mm, M11 × 0.75 mm, M11 × 1 mm, M11 × 1.5 mm, M12 × 1 mm, M12 × 1.25 mm, M12 × 1.5 mm, M12 × 1.75 mm, M14 × 1.25 mm, M14 × 1.5 mm, M14 × 2 mm | M8, M9, M10, M11, M12, M14 | __ | __ | 5 1/8" | 5 3/8" | 1/8" | 000000000 | 00000 |
| Screws, Bolts, Threaded Rods, Drill Bits | Metric | External | M2 × 0.25 mm, M2 × 0.4 mm, M2.2 × 0.25 mm, M2.2 × 0.45 mm, M2.5 × 0.35 mm, M2.5 × 0.45 mm, M3 × 0.35 mm, M3 × 0.5 mm, M3.5 × 0.35 mm, M3.5 × 0.6 mm, M4 × 0.5 mm, M4 × 0.7 mm, M4.5 × 0.5 mm, M4.5 × 0.75 mm, M5 × 0.5 mm, M5 × 0.8 mm, M5.5 × 0.5 mm, M6 × 0.75 mm, M6 × 1 mm, M7 × 0.75 mm, M7 × 1 mm | M2, M2.2, M2.5, M3, M3.5, M4, M4.5, M5, M5.5, M6, M7 | __ | 7/32", 52 ga, 50 ga, 48 ga, 46 ga, 45 ga, 43 ga, 39 ga, 37 ga, 32 ga, 31 ga, 30 ga, 28 ga, 25 ga, 22 ga, 21 ga, 18 ga, 16 ga, 10 ga, 8 ga, 4 ga, B, D, J | 3" | 5 3/8" | 3/32" | 000000000 | 00000 |
Thread Identifier Sets
Set includes calipers and gauges to identify external and internal threads.
Container | |||||||
|---|---|---|---|---|---|---|---|
| For Use With | For Thread Type | For Thread Location | Type | Material | Includes | Each | |
Inch, Metric | |||||||
Steel | |||||||
| Screws, Bolts, Threaded Rods, Nuts, Pipe | NPT, UNC, UNF, BSPT, BSPP, Metric | External/Internal | Folding Case | Plastic | Caliper, Instruction Book, Two Steel Angle Gauges, Two Steel Gauges | 000000 | 000000 |
Thread-It Screw, Bolt, and Nut Size Identifiers
Thread your fastener into holes or onto plugs for quick and accurate size identification.
| For Use With | For Thread Type | For Thread Location | For Thread Size | Each | |
Inch | |||||
|---|---|---|---|---|---|
Steel | |||||
| Screws, Bolts, Threaded Rods, Nuts | UNC/UNF | External/Internal | 6-32, 6-40, 8-32, 10-24, 10-32, 1/4"-20, 1/4"-28, 5/16"-18, 5/16"-24, 3/8"-16, 3/8"-24, 7/16"-14, 7/16"-20, 1/2"-13, 1/2"-20, 9/16"-12, 9/16"-18, 5/8"-11, 5/8"-18, 3/4"-10, 3/4"-16, 1"-8, 1"-12 | 00000000 | 000000 |
Inch/Metric | |||||
Steel | |||||
| Screws, Bolts, Threaded Rods, Nuts | UNC/UNF/Metric | External/Internal | 6-32, 8-32, 10-24, 10-32, 1/4"-20, 1/4"-28, 5/16"-18, 5/16"-24, 3/8"-16, 3/8"-24, 7/16"-14, 7/16"-20, 1/2"-13, 1/2"-20, M4 × 0.7 mm, M5 × 0.8 mm, M6 × 1 mm, M7 × 1 mm, M8 × 1 mm, M8 × 1.25 mm, M10 × 1 mm, M10 × 1.25 mm, M10 × 1.5 mm, M12 × 1.25 mm, M12 × 1.5 mm, M12 × 1.75 mm | 00000000 | 00000 |
Metric | |||||
Steel | |||||
| Screws, Bolts, Threaded Rods, Nuts | Metric | External/Internal | M3 × 0.5 mm, M4 × 0.7 mm, M5 × 0.8 mm, M6 × 1 mm, M7 × 1 mm, M8 × 1 mm, M8 × 1.25 mm, M10 × 1 mm, M10 × 1.25 mm, M10 × 1.5 mm, M12 × 1.25 mm, M12 × 1.5 mm, M12 × 1.75 mm, M14 × 1.5 mm, M14 × 2 mm, M16 × 1.5 mm, M16 × 2 mm, M20 × 1.5 mm, M20 × 2.5 mm, M24 × 2 mm, M24 × 3 mm | 00000000 | 00000 |
Wall-Mount Thread-It Screw, Bolt, and Nut Size Identifiers
Mount to a wall for easy access, and thread your fastener into holes or onto plugs for quick and accurate size identification.
Mounting Holes | |||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|
| For Use With | For Thread Type | For Thread Location | For Thread Size | Wd. | Ht. | Thick. | No. of | Hole Dia. | Fasteners Included | Each | |
Inch/Metric | |||||||||||
Steel | |||||||||||
| Screws, Bolts, Threaded Rods, Nuts | UNC/UNF/Metric | External/Internal | 6-32, 8-32, 10-24, 10-32, 1/4"-20, 1/4"-28, 5/16"-18, 5/16"-24, 3/8"-16, 3/8"-24, 7/16"-20, 1/2"-13, 1/2"-20, 9/16"-12, 9/16"-18, M4 × 0.7 mm, M5 × 0.8 mm, M6 × 1 mm, M7 × 1 mm, M8 × 1 mm, M8 × 1.25 mm, M10 × 1 mm, M10 × 1.25 mm, M10 × 1.5 mm, M12 × 1.25 mm, M12 × 1.5 mm, M12 × 1.75 mm, 7/16"-14 | 3" | 39" | 1/2" | 3 | 5/16" | No | 00000000 | 000000 |
Threads per Inch and Thread Pitch Identifiers
Determine threads per inch and thread pitch on a variety of external and internal threads.
Folded | |||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|
| For Use With | For Thread Type | For Thread Location | For Threads per Inch | For Thread Pitch | No. of Identifiers | Lg. | Wd. | Manufacturer | Manufacturer Model No. | Each | |
Inch | |||||||||||
Steel | |||||||||||
| Screws, Bolts, Threaded Rods | BSW | External/Internal | 4, 4 1/2, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 16, 18, 19, 20, 22, 24, 25, 26, 28, 30, 32, 34, 36, 40, 48, 60 | __ | 28 | 2 3/4" | 3/4" | Mitutoyo | 188-102 | 000000 | 000000 |
| Screws, Bolts, Threaded Rods | BSW | External/Internal | 4, 4 1/2, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 16, 18, 19, 20, 22, 24, 25, 26, 28, 30, 32, 36, 40, 48, 60, 62 | __ | 28 | 2 3/4" | 1/2" | __ | __ | 0000000 | 00000 |
| Screws, Bolts, Threaded Rods, Nuts | UNC/UNF | External/Internal | 4, 4 1/2, 5, 5 1/2, 6, 7, 8, 9, 10, 11, 11 1/2, 12, 13, 14, 15, 16, 18, 20, 22, 24, 26, 27, 28, 30, 32, 34, 36, 38, 40, 42 | __ | 30 | 2 3/4" | 1/2" | __ | __ | 0000000 | 00000 |
| Screws, Bolts, Threaded Rods, Nuts | UNC/UNF | External/Internal | 4, 4 1/2, 5, 5 1/2, 6, 7, 8, 9, 10, 11, 11 1/2, 12, 13, 14, 15, 16, 18, 20, 22, 24, 26, 27, 28, 30, 32, 34, 36, 38, 40, 42, 44, 46, 48, 50, 52, 54, 56, 58, 60, 62, 64, 66, 68, 70, 72, 74, 76, 78, 80, 82, 84 | __ | 51 | 2 1/4" | 2 1/4" | __ | __ | 0000000 | 00000 |
| Screws, Bolts, Threaded Rods, Nuts | UNC/UNF | External/Internal | 6, 7, 8, 9, 10, 11, 11 1/2, 12, 13, 14, 15, 16, 18, 20, 22, 24, 26, 27, 28, 30, 32, 34, 36, 38, 40, 42, 48, 50, 56, 60 | __ | 30 | 2 3/4" | 1/2" | __ | __ | 000000 | 00000 |
| Screws, Bolts, Threaded Rods, Nuts | UNC/UNF | External/Internal | 9, 10, 11, 11 1/2, 12, 13, 14, 15, 16, 18, 20, 22, 24, 26, 27, 28, 30, 32, 34, 36, 38, 40 | __ | 22 | 2 3/4" | 1/2" | __ | __ | 000000 | 00000 |
Stainless Steel | |||||||||||
| Screws, Bolts, Threaded Rods, Nuts | Acme | External/Internal | 1, 1 1/3, 1 1/2, 1 3/4, 2, 2 1/2, 3, 3 1/2, 4, 5, 6, 7, 8, 9, 10, 12 | __ | 16 | 4 3/4" | 1" | __ | __ | 0000000 | 000000 |
Inch/Metric | |||||||||||
Steel | |||||||||||
| Screws, Bolts, Threaded Rods, Nuts | UNC/UNF/Metric | External/Internal | 4, 4 1/2, 5, 5 1/2, 6, 7, 8, 9, 10, 11, 11 1/2, 12, 13, 14, 15, 16, 18, 20, 22, 24, 26, 28, 29, 30, 32, 34, 36, 38, 40, 42 | 0.4 mm, 0.5 mm, 0.7 mm, 0.75 mm, 0.8 mm, 0.9 mm, 1 mm, 1.25 mm, 1.5 mm, 1.75 mm, 2 mm, 2.5 mm, 3 mm, 3.5 mm, 4 mm, 4.5 mm, 5 mm, 5.5 mm, 6 mm, 6.5 mm, 7 mm | 51 | 2 3/4" | 1/2" | __ | __ | 0000000 | 00000 |
| Screws, Bolts, Threaded Rods, Nuts | UNC/UNF/Metric | External/Internal | 4, 6, 8, 10, 11, 11 1/2, 12, 13, 16, 20, 28, 32, 40, 56 | 0.5 mm, 0.75 mm, 1 mm, 1.25 mm, 1.5 mm, 1.75 mm, 2 mm, 2.5 mm, 3 mm, 3.5 mm, 4 mm, 4.5 mm, 5 mm, 6 mm | 28 | 2 3/4" | 1/2" | __ | __ | 0000000 | 00000 |
Metric | |||||||||||
Steel | |||||||||||
| Screws, Bolts, Threaded Rods, Nuts | Metric | External/Internal | __ | 0.25 mm, 0.3 mm, 0.35 mm, 0.4 mm, 0.45 mm, 0.5 mm, 0.55 mm, 0.6 mm, 0.65 mm, 0.7 mm, 0.75 mm, 0.8 mm, 0.85 mm, 0.9 mm, 1 mm, 1.1 mm, 1.2 mm, 1.25 mm, 1.3 mm, 1.4 mm, 1.5 mm, 1.6 mm, 1.7 mm, 1.75 mm, 1.8 mm, 1.9 mm, 2 mm, 2.5 mm | 28 | 2 1/2" | 1/2" | Starrett | 156M | 0000000 | 00000 |
| Screws, Bolts, Threaded Rods, Nuts | Metric | External/Internal | __ | 0.25 mm, 0.3 mm, 0.35 mm, 0.4 mm, 0.45 mm, 0.5 mm, 0.55 mm, 0.6 mm, 0.65 mm, 0.7 mm, 0.75 mm, 0.8 mm, 0.85 mm, 0.9 mm, 1 mm, 1.1 mm, 1.2 mm, 1.25 mm, 1.3 mm, 1.4 mm, 1.5 mm, 1.6 mm, 1.7 mm, 1.75 mm, 1.8 mm, 1.9 mm, 2 mm, 2.5 mm | 28 | 2 3/4" | 1/2" | __ | __ | 0000000 | 00000 |
| Screws, Bolts, Threaded Rods, Nuts | Metric | External/Internal | __ | 0.4 mm, 0.5 mm, 0.6 mm, 0.7 mm, 0.75 mm, 0.8 mm, 0.9 mm, 1 mm, 1.25 mm, 1.5 mm, 1.75 mm, 2 mm, 2.5 mm, 3 mm, 3.5 mm, 4 mm, 4.5 mm, 5 mm, 5.5 mm, 6 mm, 6.5 mm, 7 mm | 22 | 2 3/4" | 1/2" | __ | __ | 0000000 | 00000 |
Screw, Bolt, and Nut Size Identifiers
Inch
Inch/Metric
Metric
Use on external and internal fastener threads.
| For Use With | For Thread Type | For Thread Location | For Screw Size | For Thread Pitch | For Nut Size | Wd. | Ht. | Thick. | Each | |
Inch | ||||||||||
|---|---|---|---|---|---|---|---|---|---|---|
Plastic | ||||||||||
| Screws, Bolts, Threaded Rods, Nuts | __ | External/Internal | No. 8, No. 10, 1/4", 5/16", 3/8", 7/16", 1/2", 9/16", 5/8", 3/4" | __ | No. 8, No. 10, 1/4", 5/16", 3/8", 7/16", 1/2", 9/16", 5/8" | 7 1/2" | 2 3/8" | 1/64" | 000000000 | 00000 |
Inch/Metric | ||||||||||
Plastic | ||||||||||
| Screws, Bolts, Threaded Rods, Nuts | __ | External/Internal | No. 6, No. 8, No. 10, 1/4", 5/16", 3/8", 7/16", 1/2", 9/16", 5/8", 3/4", 1", M6, M7, M8, M10, M12, M14, M16, M18, M20, M22 | __ | No. 8, No. 10, 1/4", 5/16", 3/8", 7/16", 1/2", 9/16", 5/8" | 9" | 3 3/4" | 1/64" | 000000000 | 00000 |
Metric | ||||||||||
Plastic | ||||||||||
| Screws, Bolts, Threaded Rods, Nuts | Metric | External/Internal | M6, M7, M8, M10, M12, M14, M16 | 1 mm, 1.25 mm, 1.5 mm, 1.75 mm, 2 mm | M10, M11, M13, M17, M19, M22, M24 | 5 1/4" | 3 3/16" | 1/64" | 000000000 | 0000 |
Threads per Inch and Center Identifiers
Identify threads per inch on external threads and find the center of your workpiece to line up thread-cutting tools. This identifier has a corrosion-resistant satin-chrome finish that reduces glare.
| For Use With | For Thread Type | For Thread Location | For Threads per Inch | Lg. | Wd. | Thick. | Each | |
Inch | ||||||||
|---|---|---|---|---|---|---|---|---|
Satin-Chrome Steel | ||||||||
| Screws, Bolts, Threaded Rods | UNC/UNF | External | 14, 20, 24, 32 | 2 1/4" | 3/4" | 3/64" | 0000000 | 000000 |
Acme Thread Identifiers
Identify Acme threads and use as a guide while grinding and cutting Acme threads to a 29° included angle.
| For Use With | For Thread Location | For Threads per Inch | Wd. | Ht. | Thick. | Each | |
Steel | |||||||
|---|---|---|---|---|---|---|---|
| Screws, Bolts, Threaded Rods | External | 1, 1 1/3, 1 1/2, 1 3/4, 2, 2 1/2, 3, 4, 5, 6, 7, 8, 9, 10 | 3 3/8" | 1 5/8" | 7/64" | 0000000 | 000000 |
Drill Bit Size Identifiers
Wire Gauge
Measure drill bit sizes with these identifiers.
Drill/tap identifier includes a tap size conversion chart.
| For System of Measurement | For Use With | For Drill Bit Size | Wd. | Ht. | Thick. | Material | Color | Mounting Hole Dia. | Each | |
| Wire Gauge | Drills/Taps | 60 ga, 59 ga, 58 ga, 57 ga, 56 ga, 55 ga, 54 ga, 53 ga, 52 ga, 51 ga, 50 ga, 49 ga, 48 ga, 47 ga, 46 ga, 45 ga, 44 ga, 43 ga, 42 ga, 41 ga, 40 ga, 39 ga, 38 ga, 37 ga, 36 ga, 35 ga, 34 ga, 33 ga, 32 ga, 31 ga, 30 ga, 29 ga, 28 ga, 27 ga, 26 ga, 25 ga, 24 ga, 23 ga, 22 ga, 21 ga, 20 ga, 19 ga, 18 ga, 17 ga, 16 ga, 15 ga, 14 ga, 13 ga, 12 ga, 11 ga, 10 ga, 9 ga, 8 ga, 7 ga, 6 ga, 5 ga, 4 ga, 3 ga, 2 ga, 1 ga | 2 1/2" | 6 1/2" | 5/64" | Steel | Silver | 1/8" | 0000000 | 000000 |
Pipe Thread Identifiers
Check external NPT thread size and taper.
| For Thread Type | For Thread Location | For Pipe Size | Wd. | Ht. | Thick. | Color | Each | |
Aluminum | ||||||||
|---|---|---|---|---|---|---|---|---|
| NPT | External | 1/16, 1/8, 1/4, 3/8, 1/2 | 2" | 3" | 1/4" | Blue | 000000 | 000000 |
Threads per Inch and Thread Pitch Size Checkers
Inspect fasteners and verify threads with this checker. It includes three wires for each of the pitch diameters. Select the wire that best fits the threads; then calculate the pitch diameter with the equations provided.
Wire | ||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| For Use With | For Thread Type | For Thread Location | For Threads per Inch | For Thread Pitch | For Acme Threads per Inch | No. of Wires | Lg. | Material | Container | Container Material | Each | |
Inch; Metric | ||||||||||||
| Screws, Bolts, Threaded Rods, Pipe | NPT, UNC, UNF, Metric, Acme | External | 3, 3 1/2, 4, 4 1/2, 5, 5 1/2, 6, 7, 7 1/2, 8, 9, 10, 11, 11 1/2, 12, 13, 14, 16, 18, 20, 24, 27, 28, 32, 36, 40, 44, 48 | 0.5 mm, 0.6 mm, 0.7 mm, 0.75 mm, 0.8 mm, 1 mm, 1.25 mm, 1.5 mm, 1.75 mm, 2 mm, 2.5 mm, 3 mm, 3.5 mm, 4 mm, 4.5 mm, 5 mm, 5.5 mm, 6 mm | 3, 4, 5, 6, 8, 10, 12, 14, 16 | 48 | 2 3/4" | Stainless Steel | Pouch | Vinyl | 000000 | 000000 |
Tap and Drill Reference Rulers
One side of this ruler lists tap and drill sizes. The other side has a decimal equivalent table and a 6" rule.
Graduation | |||||||||
|---|---|---|---|---|---|---|---|---|---|
| Lg. | Wd. | Marks | Color | Location | Numeric Increments | Material | Features | Each | |
| 7" | 1 1/4" | 64ths | Black | Front | 8/64" | Stainless Steel | Tap and Drill Sizes for UNF, UNC, Metric ISO, and American Standard Pipe Thread Sizes Decimal Equivalent Table for 1/64" to 63/64" Hanging Hole | 0000000 | 00000 |
Thread Gauges for Lug Nuts
Identify the most common bolt thread sizes.
| For Thread Size | For Thread Location | Material | Each | |
| 7/16"-20 1/2"-20 9/16"-18 M12 × 1.25 mm M12 × 1.5 mm M12 × 1.75 mm M14 × 1.25 mm M14 × 1.5 mm M14 × 2 mm M16 × 1.5 mm | External, Internal | Aluminum | 00000000 | 000000 |