# item.guide
Side-by-Side Comparison Metric Threads (ISO)

M3 Thread vs. M5 Thread

Comparing 2 standards across 7 specifications. 7 key differences identified.

Comparing:
M3 Thread
M5 Thread

M3 is an ISO metric machine screw thread with a nominal major diameter of 3.0 mm and a standard coarse pitch of 0.50 mm. Requiring a 2.50 mm tap drill, it is the world's most widely deployed fastener in 3D printers, consumer electronics, and PC 5.25-inch optical drive bays.

View full M3 Thread spec sheet →

M5 is an ISO metric machine screw thread with a nominal major diameter of 5.0 mm and a standard coarse pitch of 0.80 mm. Requiring a 4.20 mm tap drill, it is the universal standard for bicycle water bottle cages, disc brake rotor mounts, and 2020/4040 aluminum extrusion T-slot framing nuts.

View full M5 Thread spec sheet →

Specification Comparison Table

7 Parameters
Parameter / Spec
Nominal Major Diameter
3.00 mm 5.00 mm
Standard Coarse Pitch
0.50 mm 0.80 mm
Fine Pitch (Optional)
0.35 mm 0.50 mm
Tap Drill Diameter
2.50 mm (75% thread engagement) 4.20 mm (75% thread engagement)
Minor Diameter (Internal)
2.459 mm 4.134 mm
Tensile Stress Area
5.03 mm² 14.2 mm²
Common Drive Size
PH1 / PH2 / 2.5mm Allen / T10 4.0mm Allen / T25 / PH2