M2.5 Screw Size Chart – Head Dimensions, Drive Sizes & Thread Pitch | Monster Bolts
M2.5 screw and bolt sizes are widely used in laptops, small electronics, robotics, and precision equipment. Use this chart to quickly find head height, head diameter, and drive size for popular M2.5 types. If you’re new to standards, DIN and ISO numbers are the exact identifiers that define official dimensions (e.g., DIN 912, ISO 7380). Standard coarse thread for M2.5 is M2.5-0.45.
Metric M2.5-0.45 (Coarse) – Dimensions & Drive Sizes
| Type | DIN | ISO | Head Height | Head Diameter | Drive Size |
|---|---|---|---|---|---|
| M2.5 Hex Bolts (FT) | 933 | 4017 | 1.825 mm | 5.45 mm* | 5 mm WAF |
| M2.5 Hex Bolts (PT) | 931 | 4014 | 1.825 mm | 5.45 mm* | 5 mm WAF |
| M2.5 Socket Head Cap | 912 | 4762 | 2.50 mm | 4.68 mm | 2 mm hex |
| M2.5 Low Head Socket Cap | 7984 | — | 1.6 mm | 4.5 mm | 1.5 mm hex |
| M2.5 Button Head Socket | 9427 | 7380 | 1.5 mm | 4.5 mm | 1.5 mm hex |
| M2.5 Flat Head Socket | 7991 | 10642 | 1.5 mm | 4.7 mm | 1.5 mm hex |
| M2.5 Phillips Flat Head | 965 | — | 1.5 mm | 4.7 mm | #1 Phillips |
| M2.5 Phillips Pan Head | 7985 | 7045 | 2.12 mm | 5.0 mm | #1 Phillips |
All of these pair with matching M2.5 nuts and M2.5 washers.
Legend: PT = Partial Thread, FT = Full Thread. * = Width Across Flats (hex).
- Metric Thread Pitch Table • US TPI (comparison)
- How to Measure Length & Diameter • Printable Ruler (to scale)
- Shop all M2.5 fasteners — fast shipping from Milton, Florida.
M2.5 FAQs
What hex key fits an M2.5 socket head cap screw?
Typically a 2 mm hex key. Low-head socket styles often use a 1.5 mm hex.
What nut fits an M2.5 screw?
M2.5 screws pair with M2.5 nuts and M2.5 washers. Metric sizes always match by nominal diameter.
What is the standard M2.5 thread pitch?
Standard coarse pitch is M2.5-0.45. Fine-pitch options are less common—always check your tapped hole or nut.
Is an M2.5 the same as #3 screw size?
No. While close in diameter (~0.098" vs. ~0.099"), M2.5 and #3 screws use different thread systems and are not interchangeable.