Side-by-Side Comparison
Metric Threads (ISO)
M2.5 Thread vs. M3 Thread
Comparing 2 standards across 7 specifications. 6 key differences identified.
Comparing:
M2.5 Thread
M3 Thread
M2.5 is an ISO metric machine screw thread with a nominal major diameter of 2.5 mm and a standard coarse pitch of 0.45 mm. Requiring a 2.05 mm tap drill, it is the standard fastener for 2.5-inch SATA/SAS hard drive caddies, Raspberry Pi mounting standoffs, and consumer drone frames.
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.
Specification Comparison Table
7 Parameters| Parameter / Spec | ||
|---|---|---|
|
Nominal Major Diameter
|
2.50 mm | 3.00 mm |
|
Standard Coarse Pitch
|
0.45 mm | 0.50 mm |
|
Fine Pitch (Optional)
|
0.35 mm | 0.35 mm |
|
Tap Drill Diameter
|
2.05 mm (75% thread engagement) | 2.50 mm (75% thread engagement) |
|
Minor Diameter (Internal)
|
2.013 mm | 2.459 mm |
|
Tensile Stress Area
|
3.39 mm² | 5.03 mm² |
|
Common Drive Size
|
PH1 / T8 / 2.0mm Allen | PH1 / PH2 / 2.5mm Allen / T10 |