Simply Forensic Reference Library

Toolmark

Fingerprints, Firearms & Pattern Evidence

Definition. A mark created when a tool or object contacts, presses, cuts or slides against another material.

How the term is used

Examiners may compare class characteristics and finer surface features while considering manufacturing and wear variation.

Forensic example

A forced-door mark is compared with test marks created by a submitted pry tool.

Interpretation limitation

A perceived similarity is not inherently proof of one unique source.

References and further reading

NIST OSAC forensic terminology. The explanation and example are original educational summaries; consult the cited material and current laboratory guidance for authoritative application.

Related glossary terms

ACE-VA friction-ridge comparison framework comprising Analysis, Comparison, Evaluation and Verification.Explore term Breechface MarksImpressions or markings formed on a cartridge-case head when it contacts the firearm’s breechface during firing.Explore term Class CharacteristicsFeatures shared by objects in a particular class because of design, manufacture, composition or other common properties.Explore term Fingerprint MinutiaeLocal friction-ridge features such as ridge endings and bifurcations considered during friction-ridge comparisons.Explore term

Related articles

NIST Develops New Standard to Boost Accuracy in Ballistics and Toolmark AnalysisThe National Institute of Standards and Technology (NIST) has created a new standard reference material to help forensic…Read article NIST OSAC Adds Two Firearm and Toolmark Standards in November 2026NIST’s OSAC Registry added two firearm and toolmark standards on November 3, 2026, addressing verification of source conclusions…Read article Calvin Goddard: The Comparison Microscope and the Rise of Forensic Firearm IdentificationLearn how Calvin Goddard and his collaborators advanced firearm and toolmark comparison, from early microscopy to the St.…Read article