{"openapi":"3.1.0","info":{"title":"Shaft Power API","version":"1.0.0","description":"Rotational and shaft-power maths as an API, computed locally and deterministically. The power endpoint relates mechanical power, torque and rotational speed — give any two of the power, the torque in newton-metres and the speed in rpm and it returns the third using P = T·ω with ω = 2πN/60, reporting the angular velocity and the power in watts, kilowatts, mechanical horsepower and metric horsepower (PS). The angular endpoint converts a rotational speed freely between rpm, radians per second, degrees per second and hertz (revolutions per second), and — given a radius — the tangential speed and centripetal acceleration at the rim. The units endpoint converts power across watts, kilowatts, mechanical horsepower (745.7 W), metric horsepower or PS (735.5 W), foot-pounds per second and BTU per hour. Everything is computed locally and deterministically, so it is instant and private. Ideal for automotive, motor, drivetrain, robotics and machinery app developers, engine and gearbox tools, and mechanical-engineering education. Pure local computation — no key, no third-party service, instant. Live, nothing stored. 3 endpoints. This is mechanical shaft power; for bolt tightening torque use a torque API and for electrical power factor a power-factor API.","contact":{"name":"PremiumApi","url":"https://www.oanor.com/by/premiumapi"}},"servers":[{"url":"https://api.oanor.com/shaftpower-api","description":"oanor gateway"}],"tags":[{"name":"Shaft Power"},{"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/angular":{"get":{"operationId":"get_v1_angular","tags":["Shaft Power"],"summary":"Angular velocity","description":"","parameters":[{"name":"rpm","in":"query","required":false,"description":"Speed (rpm)","schema":{"type":"string"},"example":"3000"},{"name":"rad_s","in":"query","required":false,"description":"Or angular velocity (rad/s)","schema":{"type":"string"}},{"name":"hz","in":"query","required":false,"description":"Or frequency (Hz)","schema":{"type":"string"}},{"name":"radius","in":"query","required":false,"description":"Radius (m) for tangential speed","schema":{"type":"string"},"example":"0.1"}],"security":[{"oanorKey":[]}],"responses":{"200":{"description":"OK","content":{"application/json":{"example":{"data":{"hz":50,"rpm":3000,"note":"ω = 2πN/60 (rpm) = 2π·f (Hz). Tangential speed v = ω·r; centripetal acceleration = ω²·r.","deg_s":18000,"rad_s":314.159265,"radius_m":0.1,"tangential_speed_ms":31.415927,"tangential_speed_kmh":113.097336,"centripetal_accel_ms2":9869.604401},"meta":{"timestamp":"2026-06-04T18:38:05.685Z","request_id":"ec395ada-59d9-4a31-a8b2-261159eb9e71"},"status":"ok","message":"Angular velocity","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":{"get":{"operationId":"get_v1_power","tags":["Shaft Power"],"summary":"Power / torque / rpm","description":"","parameters":[{"name":"power","in":"query","required":false,"description":"Power (W)","schema":{"type":"string"}},{"name":"power_hp","in":"query","required":false,"description":"Or power (hp)","schema":{"type":"string"}},{"name":"torque","in":"query","required":false,"description":"Torque (N·m)","schema":{"type":"string"},"example":"100"},{"name":"rpm","in":"query","required":false,"description":"Rotational speed (rpm)","schema":{"type":"string"},"example":"3000"}],"security":[{"oanorKey":[]}],"responses":{"200":{"description":"OK","content":{"application/json":{"example":{"data":{"rpm":3000,"note":"P = T·ω with ω = 2πN/60 (N in rpm). 1 hp = 745.6999 W, 1 PS = 735.499 W.","inputs":{"given":2},"power_w":31415.926536,"power_hp":42.129451,"power_kw":31.415926536,"power_ps":42.713773,"torque_nm":100,"solved_for":"power","angular_velocity_rad_s":314.159265},"meta":{"timestamp":"2026-06-04T18:38:05.796Z","request_id":"eac3688c-5d23-4546-a96b-8cfb140a3c58"},"status":"ok","message":"Power/torque/rpm","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/units":{"get":{"operationId":"get_v1_units","tags":["Shaft Power"],"summary":"Power units","description":"","parameters":[{"name":"watt","in":"query","required":false,"description":"Power (W)","schema":{"type":"string"}},{"name":"kw","in":"query","required":false,"description":"Power (kW)","schema":{"type":"string"}},{"name":"hp","in":"query","required":false,"description":"Power (hp)","schema":{"type":"string"},"example":"100"},{"name":"ps","in":"query","required":false,"description":"Power (PS)","schema":{"type":"string"}}],"security":[{"oanorKey":[]}],"responses":{"200":{"description":"OK","content":{"application/json":{"example":{"data":{"kw":74.5699872,"note":"1 hp (mechanical) = 745.699872 W, 1 PS (metric hp) = 735.49875 W, 1 ft·lbf/s = 1.35582 W.","watt":74569.9872,"btu_per_hour":254443.3581,"ft_lbf_per_s":55000.000031,"ps_metric_hp":101.386967,"hp_mechanical":100},"meta":{"timestamp":"2026-06-04T18:38:05.916Z","request_id":"7535b796-2edd-4e8e-b60b-a891b6cb62f2"},"status":"ok","message":"Power units","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":"SI units: power W, torque N·m, speed rpm, angle rad/s. 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