Screw Size Drill Bit Chart
Pilot Hole Gauge Tap Finder
Only for iPhone
Free · In‑App Purchases · Designed for iPhone. Not verified for macOS.
iPhone
Pick a screw, pick the material, get the exact pilot hole and drill bit. Metric and imperial charts, tap-drill sizes and a diameter finder, all offline.
Which drill bit for a #8 screw in hardwood? ScrewGuide answers in two taps — the complete screw, bolt and drill-bit chart with the exact pilot hole for the material in front of you, fully offline.
Printed charts give you one number and hope you guessed the material right. ScrewGuide is material-aware: pick a screw, pick softwood, hardwood, MDF/chipboard, drywall, sheet metal or plastic, and it works out the pilot, clearance and countersink diameter for that exact combination — then names the nearest real drill bit you actually own, in millimetres or inches.
WHAT YOU GET
- The right pilot hole every time, calculated per material, so boards stop splitting and screws stop stripping
- 20 screw sizes cross-referenced: metric M2-M12, US gauge #4-#14 and tapered wood screws, with major and minor diameter, thread pitch, TPI, head diameter and typical lengths
- A full 68-bit drill chart in one place: metric, fractional, number and letter bits with decimal and millimetre equivalents
- Measured something and don't know what it is? Dial in a diameter and get the nearest screw and the nearest drill bit instantly
- A metric tap-drill chart, so you can thread a hole without hunting a reference online
- Head styles and drive types decoded — Phillips, Pozidriv, Square/Robertson, Torx and hex — plus why pilot holes work at all
PERFECT FOR
- Woodworkers and carpenters who refuse to split another board
- DIYers assembling flat-pack, hanging shelves or mounting a TV
- Makers and 3D-printing hobbyists living in M3 and M4 hardware
- Trades and hobby mechanics switching between metric and imperial on the same job
WHY NOT JUST GOOGLE IT?
Because the garage has no signal, your hands are dirty and the search results argue with each other. ScrewGuide keeps every number on the device, opens instantly, and gives one clear answer per material instead of ten forum opinions. Save the sizes you use most and they are one tap away next time.
PRIVACY
No account, no sign-up, no ads, no tracking, no internet connection required. Your saved sizes and unit preference stay on your iPhone.
FULL ACCESS
Material-aware pilot, clearance and countersink sizing, the complete drill-bit chart, the tap-drill chart and the size finder unlock with full access. Choose a weekly or yearly subscription, or pay once for lifetime access — one payment, no renewal. Ten common screw sizes stay browsable for free so you can try the reference first.
Open ScrewGuide before the drill comes out and get the hole right the first time.
Terms of Use (EULA): https://web-levi.web.app/terms
Privacy Policy: https://web-levi.web.app/privacy-policy
Questions? tphuc.work@gmail.com
Ratings & Reviews
- This app hasn’t received enough ratings or reviews to display an overview.
Bug fixes and performance improvements.
Subscriptions
In-App Purchases
The developer, Phuc Pham, indicated that the app’s privacy practices may include handling of data as described below. For more information, see the developer’s privacy policy .
Data Not Collected
The developer does not collect any data from this app.
Accessibility
The developer has not yet indicated which accessibility features this app supports. Learn More
Information
- Seller
- Phuc Pham
- Size
- 23.9 MB
- Category
- Utilities
- Compatibility
Requires iOS 17.0 or later.
- iPhone
Requires iOS 17.0 or later. - Mac
Requires macOS 14.0 or later and a Mac with Apple M1 chip or later. - Apple Vision
Requires visionOS 1.0 or later.
- iPhone
- Languages
- English
- Age Rating
4+
- 4+
- In-App Purchases
Yes
- Full Fastener Guide, One-Time $29.99
- Thread Finder, Yearly $14.99
- Countersink Pro, Weekly $2.99
- Copyright
- © 2026 Phuc Pham