{"openapi":"3.1.0","info":{"title":"Quarter Mile Drag API","version":"1.0.0","description":"Quarter-mile drag-strip maths as an API, computed locally and deterministically — the classic empirical estimates a racer, tuner or car enthusiast uses to relate a car's power and weight to its performance. The et endpoint gives the predicted elapsed time and trap speed from flywheel horsepower and race weight using the standard formulas — ET = 5.825 × (weight ÷ hp) raised to the one-third, trap speed = 234 × (hp ÷ weight) raised to the one-third — so a 3,000 lb car with 300 hp is predicted to run about 12.6 seconds at 109 mph, assuming a competent launch and decent traction. The horsepower endpoint runs it in reverse: because trap speed is set by power-to-weight and barely by the launch, hp ≈ weight × (trap ÷ 234) cubed is a popular way to estimate flywheel power straight off a timeslip. The power-to-weight endpoint gives the ratio that actually decides acceleration — in horsepower per pound, horsepower per ton and watts per kilogram, the cleanest cross-unit figure — with a performance class from commuter through hot hatch and supercar to hypercar, because a light 200 hp car can beat a heavy 400 hp one. Everything is computed locally and deterministically, so it is instant and private. Ideal for drag-racing and tuner apps, car-spec and comparison tools, automotive enthusiasts and motorsport dashboards. Pure local computation — no key, no third-party service, instant. Empirical estimates assuming a good launch and traction — not a timeslip. 3 compute endpoints. For aerodynamic drag use a drag API; for gearing use a gear-ratio API.","contact":{"name":"PremiumApi","url":"https://www.oanor.com/by/premiumapi"}},"servers":[{"url":"https://api.oanor.com/quartermile-api","description":"oanor gateway"}],"tags":[{"name":"Drag"},{"name":"Meta"}],"components":{"securitySchemes":{"oanorKey":{"type":"apiKey","in":"header","name":"x-oanor-key","description":"Get your key at https://www.oanor.com/developer/keys"}}},"security":[{"oanorKey":[]}],"paths":{"/v1/et":{"get":{"operationId":"get_v1_et","tags":["Drag"],"summary":"ET and trap speed from power and weight","description":"","parameters":[{"name":"horsepower_hp","in":"query","required":true,"description":"Flywheel horsepower (hp)","schema":{"type":"string"},"example":"300"},{"name":"weight_lb","in":"query","required":true,"description":"Race weight incl. driver (lb)","schema":{"type":"string"},"example":"3000"}],"security":[{"oanorKey":[]}],"responses":{"200":{"description":"OK","content":{"application/json":{"example":{"data":{"note":"The standard drag-strip estimates: ET = 5.825 × (weight ÷ hp)^⅓ and trap speed = 234 × (hp ÷ weight)^⅓, with weight the full race weight including the driver and hp at the flywheel. They assume a competent launch and decent traction — a car that spins or bogs runs slower, while sticky tyres and a good 60-foot time beat the formula. Treat them as a sanity check, not a timeslip.","inputs":{"weight_lb":3000,"horsepower_hp":300},"trap_speed_mph":108.6,"quarter_mile_et_s":12.55},"meta":{"timestamp":"2026-06-06T23:53:55.108Z","request_id":"f4faa325-601a-4e40-986c-1206eb823301"},"status":"ok","message":"ET / trap speed","success":true}}}},"401":{"description":"Missing or invalid x-oanor-key header"},"402":{"description":"Active subscription required"},"429":{"description":"Rate-limit or monthly quota reached"},"502":{"description":"Upstream did not respond"}}}},"/v1/horsepower":{"get":{"operationId":"get_v1_horsepower","tags":["Drag"],"summary":"Estimate horsepower from a trap speed","description":"","parameters":[{"name":"trap_speed_mph","in":"query","required":true,"description":"Measured trap speed (mph)","schema":{"type":"string"},"example":"108.6"},{"name":"weight_lb","in":"query","required":true,"description":"Race weight incl. driver (lb)","schema":{"type":"string"},"example":"3000"}],"security":[{"oanorKey":[]}],"responses":{"200":{"description":"OK","content":{"application/json":{"example":{"data":{"note":"Trap speed reflects power far better than ET does, because it is set by power-to-weight and barely by the launch — so hp ≈ weight × (trap ÷ 234)³ is a popular way to estimate flywheel power from a timeslip. It is an estimate: aero, altitude and the exact weight all shift it, but two runs at very different traps with the same weight really do differ in power.","inputs":{"weight_lb":3000,"trap_speed_mph":108.6},"estimated_horsepower_hp":300},"meta":{"timestamp":"2026-06-06T23:53:55.177Z","request_id":"491aedb9-422c-4f40-820c-5108f4e58361"},"status":"ok","message":"Horsepower estimate","success":true}}}},"401":{"description":"Missing or invalid x-oanor-key header"},"402":{"description":"Active subscription required"},"429":{"description":"Rate-limit or monthly quota reached"},"502":{"description":"Upstream did not respond"}}}},"/v1/power-to-weight":{"get":{"operationId":"get_v1_power_to_weight","tags":["Drag"],"summary":"Power-to-weight ratio with class","description":"","parameters":[{"name":"horsepower_hp","in":"query","required":true,"description":"Flywheel horsepower (hp)","schema":{"type":"string"},"example":"300"},{"name":"weight_lb","in":"query","required":true,"description":"Weight (lb)","schema":{"type":"string"},"example":"3000"}],"security":[{"oanorKey":[]}],"responses":{"200":{"description":"OK","content":{"application/json":{"example":{"data":{"kw":223.7,"note":"Power-to-weight, not raw power, decides acceleration: a light 200 hp car can outrun a heavy 400 hp one. W/kg is the cleanest cross-unit figure (a hot hatch is ~120–180 W/kg, a supercar 250+). Shedding weight helps everywhere — acceleration, braking and cornering — while extra power only helps in a straight line.","inputs":{"weight_lb":3000,"horsepower_hp":300},"w_per_kg":164.4,"hp_per_lb":0.1,"weight_kg":1360.8,"hp_per_ton":200,"performance_class":"hot hatch / sports car"},"meta":{"timestamp":"2026-06-06T23:53:55.275Z","request_id":"69ba06b7-5a79-401f-9699-fa556383c6c7"},"status":"ok","message":"Power-to-weight","success":true}}}},"401":{"description":"Missing or invalid x-oanor-key header"},"402":{"description":"Active subscription required"},"429":{"description":"Rate-limit or monthly quota reached"},"502":{"description":"Upstream did not respond"}}}},"/v1/meta":{"get":{"operationId":"get_v1_meta","tags":["Meta"],"summary":"Spec","description":"","parameters":[],"security":[{"oanorKey":[]}],"responses":{"200":{"description":"OK","content":{"application/json":{"example":{"data":{"notes":"US units (hp, lb, mph). ET = 5.825·(wt/hp)^⅓; trap = 234·(hp/wt)^⅓; hp ≈ wt·(trap/234)³. Empirical estimates assuming a good launch and traction — not a timeslip. For aerodynamic drag use a drag API; for gearing use a gear-ratio API.","service":"quartermile-api","endpoints":{"GET /v1/et":"ET and trap speed from flywheel horsepower and race weight.","GET /v1/meta":"This document.","GET /v1/horsepower":"Estimate horsepower from a measured trap speed and weight.","GET /v1/power-to-weight":"Power-to-weight ratio (hp/lb, hp/ton, W/kg) with a class."},"description":"Quarter-mile drag-strip maths: elapsed time and trap speed from power and weight, horsepower from a trap speed, and power-to-weight ratio."},"meta":{"timestamp":"2026-06-06T23:53:55.348Z","request_id":"7a1430c6-dd0a-4786-a82a-41ff9543b733"},"status":"ok","message":"Meta","success":true}}}},"401":{"description":"Missing or invalid x-oanor-key header"},"402":{"description":"Active subscription required"},"429":{"description":"Rate-limit or monthly quota reached"},"502":{"description":"Upstream did not respond"}}}}},"x-oanor-pricing":[{"slug":"free","name":"Free","price_cents_month":0,"monthly_call_quota":6700,"rps_limit":2,"hard_limit":true},{"slug":"starter","name":"Starter","price_cents_month":990,"monthly_call_quota":71000,"rps_limit":6,"hard_limit":true},{"slug":"pro","name":"Pro","price_cents_month":3150,"monthly_call_quota":295000,"rps_limit":15,"hard_limit":true},{"slug":"mega","name":"Mega","price_cents_month":9800,"monthly_call_quota":1420000,"rps_limit":40,"hard_limit":true}],"x-oanor-marketplace-url":"https://www.oanor.com/api/quartermile-api"}