How it works · Accuracy & data

Know the screw. Skip the guesswork.

Place a screw against the visual outline, mark its edges, and compare it with a carefully sourced catalog. The result is a practical starting point—not engineering advice.

The identification flow

Start immediately. Add precision when you need it.

01

Measure four dimensions

Move two handles to each edge. Calibration improves physical accuracy, but estimate mode is always available.

02

Describe what you see

Choose simple visual traits. Specialist thread details remain optional.

03

Compare likely matches

Review ranked catalog records, dimensional differences, sources, and confidence.

04

Calibrate when useful

Match a real credit card or known length once and reuse that scale on the same display.

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.

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 stored locally and include source and licence metadata. External purchase links are non-affiliate, clearly marked, and may change after their verification date.

Screw identify chart

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.
Screw typeDistinguishing featuresTypical uses
Wood screwPointed tip and coarse threadTimber, furniture, and cabinetry
Machine screwUniform threaded body for a tapped hole or nutAppliances, brackets, and machinery
Sheet-metal screwSharp screw that forms or cuts threads in thin materialSheet metal, ducts, and light brackets
Drywall screwBugle-shaped head with coarse or fine threadDrywall board attached to suitable framing
Socket-cap screwCylindrical head with a hexagonal recess; ISO 4762 examplesTools, fixtures, and precision assemblies
Thumb screwEnlarged grip for adjustment by handCovers, 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

Distinguishing features
Sharp screw that forms or cuts threads in thin material
Typical uses
Sheet metal, ducts, and light brackets

Drywall screw

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

Distinguishing features
Enlarged grip for adjustment by hand
Typical uses
Covers, jigs, and adjustable fixtures