What this tool answers
You need a first-pass mechanic creeper capacity before buying a rolling under-car creeper. The calculator estimates required capacity as body_lb + tools_lb, then names the smallest class on this site’s ladder (300, 400, or 450 lb) that clears the estimate. It is not an under-car lift procedure, floor study, or substitute for manufacturer instructions.
The body + tools screening rule
Required capacity = body_lb + tools_lb. Include tools and parts that ride on the creeper with you. Tools may be zero; body weight must be greater than zero for a valid estimate.
Nameplate capacity
Listings quote a maximum working load in pounds. Confirm the live published capacity before you buy. Never exceed the nameplate for the load you intend to put on the creeper.
Flat floor, chocks, and jack stands
Use the creeper on a flat floor. Chock the vehicle before working underneath. A creeper is not a jack stand — support the vehicle with rated jack stands. This site does not certify lifts or shop setups.
Class ladder on this site
Classes are returned as rated pounds: 300, 400, and 450 lb. The tool picks the smallest class whose rated_lb is greater than or equal to required_lb. Inputs are body weight and tools/parts weight in pounds.
When the answer is NO_MATCH
If required capacity exceeds 450 lb (for example body 420 + tools 50 → required 470), this site returns NO_MATCH for its published class ladder. Typical next steps: a higher-rated industrial creeper or a different work plan. Do not force an undersized consumer creeper.
Safety notes
Never exceed nameplate. Use on a flat floor. Chock the vehicle. A creeper is not a jack stand. Keep people clear of the vehicle path. This site does not certify under-car work.
Sources
Shop practice of sizing creepers to combined rider and tool load. Manufacturer safety culture around rated equipment and proper vehicle support. VEVOR US mechanic creeper product pages for rated classes dated in products.json (checked 2026-09-10).