What is the proper name for a wrench?
In everyday use, the tool you’re asking about is called a wrench in American English and a spanner in British English. The generic term describes a hand tool designed to turn nuts and bolts by applying torque, with many specific variants for different fasteners and tasks.
Regional naming conventions
The distinction between wrench and spanner is largely geographic. Engineers and manufacturers use both terms to describe the same family of hand tools, though catalogs and brands may prefer one term over the other.
United States and Canada
In North America, "wrench" is the standard umbrella term. Many specific tools carry additional descriptors, such as "adjustable wrench," "socket wrench," or "torque wrench."
- Open-end wrench — two flat, U-shaped jaws that grip two sides of a bolt head or nut.
- Box-end wrench — an enclosed ring that seats around the head of a bolt or nut for a stronger grip.
- Combination wrench — one open-end and one box-end jaw on opposite ends.
- Adjustable wrench (Crescent wrench) — one jaw that can be adjusted to fit various sizes.
- Socket wrench — uses a handle with a removable socket to fit different fasteners, often used with a ratchet.
- Torque wrench — designed to apply a precise amount of torque to fasteners.
- Allen wrench (hex key) — L-shaped tool used to drive hexagonal socket screws; often called hex keys.
- Pipe wrench — a heavy, adjustable wrench used for gripping round pipes.
Wrench-related terms may also appear in brand names (e.g., Crescent wrench) but generic usage remains dominant in ordinary speech.
United Kingdom and Commonwealth countries
In the UK and many other Commonwealth nations, "spanner" is the conventional term. The same types exist, though naming can be slightly different (for example, "Allen key" is common, rather than "Allen wrench").
- Open-ended spanner
- Ring spanner (box-end) and double-ended open-ended spanner
- Combination spanner
- Adjustable spanner
- Socket spanner set
- Torque spanner
- Allen key (hex key)
- Pipe wrench
Despite regional word choices, mechanics and suppliers typically understand both terms, with catalogs listing equivalents in parentheses or cross-references.
How to choose the right wrench
Choosing the right wrench depends on fastener size, the space available, and whether you need torque control. In practice, professionals keep several types on hand to cover most jobs.
- Measure the fastener size to select the correct wrench size or range.
- Prefer a socket set for tight spaces or multiple fasteners in a row.
- Use a torque wrench when specifications require exact tightness.
- When space is limited, a stubby or angled handle may help.
Having the right tool reduces the risk of rounding off fasteners and saves time on repairs and maintenance.
Summary
The proper generic name for the tool is wrench in American English and spanner in British English. Beyond regional terminology, there are many specialized variants designed to fit different fasteners and tasks. Understanding the terminology helps in selecting the right tool and following job plans accurately.
