How it works · Accuracy & data
Know the screw. Skip the guesswork.
Enter measured dimensions and visible features, then compare them with a carefully sourced catalog. The result is a practical starting point—not engineering advice.
Terms of use
These terms describe appropriate use of Screw Identify and the limits of its identification guidance.
- Identification guidance. Suggested matches and similarity scores are not guarantees of identity, fit, strength, or suitability. Check dimensions, thread details, materials, and original specifications before choosing or using a replacement.
- Safety-critical uses. Do not rely on this tool alone for structural, load-bearing, automotive, electrical, or other safety-critical applications. Consult the manufacturer’s specifications and an appropriately qualified professional.
- Responsible use. Use the website lawfully. Do not interfere with its operation, attempt unauthorized access, or send requests intended to disrupt the service.
- Sources and licences. Respect the attribution and licence conditions shown with catalog images and source material. Availability on this website does not grant unrestricted rights to reuse third-party content.
- External websites. Source and supplier links are provided for reference. Their content, availability, purchases, and services are governed by the relevant third party’s terms.
- Service limitations. Catalog coverage is incomplete, and errors or interruptions can occur. Features and catalog content may change as the tool is maintained.
Nothing in these terms removes rights or protections that cannot be excluded under applicable law.
See our Privacy policy for information about data handling. For questions or to report an error, contact us.
The identification flow
Start immediately. Add precision when you need it.
Measure four dimensions
Move two handles to each edge. Calibration improves physical accuracy, but estimate mode is always available.
Describe what you see
Choose simple visual traits. Specialist thread details remain optional.
Compare likely matches
Review ranked catalog records, dimensional differences, sources, and confidence.
Calibrate when useful
Reuse saved calibration while the display setup is unchanged; check it again after display or zoom changes.
Measurement accuracy
CSS pixels do not have a guaranteed physical size. Display density, zoom, operating-system scaling, and browser behavior can all change apparent measurements. Without calibration, the workspace is clearly labelled as an estimate. Screw Identify saves one local pixels-per-millimetre calibration and warns when detectable display characteristics change.
With valid calibration, the workspace preserves the calibrated scale instead of shrinking to fit. Scroll in normal view if needed; fullscreen is available only when the whole workspace fits.
Why calibration is manual
Browser information can describe the display context, but it cannot reliably tell whether a screen is physically 14 inches or 27 inches. Matching a real credit card or known length establishes that physical scale. Calibration is recommended, never required.
Catalog quality
The pilot separates verified records from examples and keeps source references with each variant. Unknown characteristics never become hidden assumptions.
Images and links
Reference images are served through this website and include source and licence metadata.
External purchase links are non-affiliate, clearly marked, and may change after their verification date.
Screw identify chart
| Screw type | Distinguishing features | Typical uses |
|---|---|---|
| Wood screw | Pointed tip and coarse thread | Timber, furniture, and cabinetry |
| Machine screw | Uniform threaded body for a tapped hole or nut | Appliances, brackets, and machinery |
| Sheet-metal screw Specifications need verification | Sharp screw that forms or cuts threads in thin material | Sheet metal, ducts, and light brackets |
| Drywall screw Specifications need verification | Bugle-shaped head with coarse or fine thread | Drywall board attached to suitable framing |
| Socket-cap screw | Cylindrical head with a hexagonal recess; ISO 4762 examples | Tools, fixtures, and precision assemblies |
| Thumb screw Specifications need verification | Enlarged grip for adjustment by hand | Covers, jigs, and adjustable fixtures |
Use this chart as a visual starting point, not a complete size list. These families are represented in the current catalog, but not every size, material, or head variation is available. Typical uses describe common applications; they do not establish load capacity or suitability for your project. Follow the linked references for further details.
Wood screw
- Distinguishing features
- Pointed tip and coarse thread
- Typical uses
- Timber, furniture, and cabinetry
Machine screw
- Distinguishing features
- Uniform threaded body for a tapped hole or nut
- Typical uses
- Appliances, brackets, and machinery
Sheet-metal screw
Specifications need verification
- Distinguishing features
- Sharp screw that forms or cuts threads in thin material
- Typical uses
- Sheet metal, ducts, and light brackets
Drywall screw
Specifications need verification
- Distinguishing features
- Bugle-shaped head with coarse or fine thread
- Typical uses
- Drywall board attached to suitable framing
Socket-cap screw
- Distinguishing features
- Cylindrical head with a hexagonal recess; ISO 4762 examples
- Typical uses
- Tools, fixtures, and precision assemblies
Thumb screw
Specifications need verification
- Distinguishing features
- Enlarged grip for adjustment by hand
- Typical uses
- Covers, jigs, and adjustable fixtures