{"uid":"cap_9YDFcSmXignJQnqNvTJ1j","slug":"bicycle-gearing-fit-calc-cadence-for-speed-de2d7b53","name":"Bicycle Gearing & Fit Calc – Cadence for Speed","description":"Cadence needed to hold a target speed in a given gear, and the chainring-to-cog ratio needed for a speed at a cadence.","url":"https://bike-calc.x402tookit.com/cadence-for-speed?utm_source=zero.xyz","method":"GET","headers":{},"bodySchema":{"type":"object","$schema":"https://json-schema.org/draft/2020-12/schema","required":["input"],"properties":{"input":{"type":"object","required":["type","method"],"properties":{"type":{"type":"string","const":"http"},"method":{"enum":["GET"],"type":"string"},"queryParams":{"type":"object","required":[],"properties":{"cog":{"type":"integer","description":"Rear cog teeth"},"wheel":{"type":"string","description":"Tyre preset: 700x23c, 700x25c, 700x28c, 700x32c, 700x35c, 700x38c, 26x2.0 (default 700x25c)"},"cadence":{"type":"number","description":"Cadence in rpm, to get the ratio needed (default 90)"},"speedKmh":{"type":"number","description":"Target speed in km/h (use speedKmh or speedMph)"},"speedMph":{"type":"number","description":"Target speed in mph"},"chainring":{"type":"integer","description":"Chainring teeth, to get the cadence for that gear"},"circumferenceMm":{"type":"number","description":"Rolling circumference in mm instead of a preset"}}}},"additionalProperties":false},"output":{"type":"object","required":["type"],"properties":{"type":{"type":"string"},"example":{"type":"object","properties":{"cog":{"type":["null","number"]},"asOf":{"type":["null","string"]},"source":{"type":["null","string"]},"reasons":{"type":["array","null"],"items":{"type":"string"}},"summary":{"type":["null","string"]},"verdict":{"type":["null","string"]},"degraded":{"type":["boolean","null"]},"speedKmh":{"type":["null","number"]},"speedMph":{"type":["null","number"]},"chainring":{"type":["null","number"]},"disclaimer":{"type":["null","string"]},"notChecked":{"type":["array","null"],"items":{"type":"string"}},"atCadenceRpm":{"type":["null","number"]},"circumferenceMm":{"type":["null","number"]},"cadenceNeededRpm":{"type":["null","number"]},"requiredRatioAtCadence":{"type":["null","number"]},"requiredDevelopmentAtCadenceMeters":{"type":["null","number"]}}}}}}},"responseSchema":null,"example":null,"exampleRequest":null,"tags":["x402"],"displayCostAmount":"0.02","displayCostAsset":"USDC","priceDynamic":false,"priceHint":null,"priceStatus":"priced","priceSource":"probe","requiresHandshake":false,"reviewCount":0,"rating":{"score":"0.00","successRate":"0.00","reviews":0,"stars":null,"state":"unrated"},"availabilityStatus":"unknown","priceObserved":null,"sessionDeposit":null,"pricing":{"kind":"static","summary":"$0.02/call","primary":{"kind":"static","protocol":"x402","network":"base","amountUsd":"0.02","per":"call","confidence":"exact"},"accepted":[{"kind":"static","protocol":"x402","network":"base","amountUsd":"0.02","per":"call","confidence":"exact"}]},"paymentMethods":[{"uid":"pm_Qhre2z9M9SZnAnoiELk51","protocol":"x402","methodType":"crypto","chain":"base","mode":"charge","costAmount":"0.02","costPer":"request","priority":0,"asset":"0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913","unit":"request","depositMicros":null,"planRef":null}],"brandName":null,"brandSlug":null,"brandBaseUrl":null,"brandDocsUrl":null,"whatItDoes":"Calculates the cadence needed to hold a target speed in a given gear, or the chainring-to-cog ratio needed to reach a target speed at a given cadence.","exampleAgentPrompt":"What cadence do I need to hold 30 km/h with a 50-tooth chainring and 17-tooth cog on 700x25c tyres?","exampleUseCases":[{"title":"Road cyclist pace planning","prompt":"I'm targeting 35 km/h on a flat stage with my 50×16 gear and 700x25c tyres — what cadence do I need to maintain that speed?"},{"title":"Finding ideal gear ratio for target speed","prompt":"I want to cruise at 28 km/h at 90 rpm on my 700x28c road bike. What chainring-to-cog ratio do I need?"},{"title":"Mountain bike speed check","prompt":"With a 34-tooth chainring, 28-tooth cog, and 26x2.0 tyres, how fast will I go at 75 rpm and what cadence do I need for 20 km/h?"}],"resultDescription":"Returns the cadence needed (rpm) to hold the target speed in the specified gear, and/or the required chainring-to-cog ratio and development (meters per pedal stroke) to reach the target speed at the given cadence, along with the speed echoed back in both km/h and mph and the rolling circumference used.","failureModes":["Missing required speed parameter (speedKmh or speedMph) returns an error","Missing chainring or cog teeth when computing cadence causes incomplete results","Invalid tyre preset string returns an error or falls back to default 700x25c","Non-positive or zero values for teeth or speed may produce nonsensical results","Conflicting circumferenceMm and wheel preset — one overrides the other without warning"],"whenToPreferThis":"Use this endpoint when you need to compute cycling cadence or gear ratio for a specific speed target, given a known chainring-cog combination and tyre size. Prefer this over a full drivetrain matrix endpoint when you only need the single-gear cadence or ratio result rather than a comparison across all gears.","instructions":null,"reviewSummary":null,"reviewSummaryHighlights":null,"reviewSummaryConcerns":null,"reviewSummaryGeneratedAt":null,"activationCount":0,"lastUsedAt":null,"lastSuccessfullyRanAt":null,"lastHealthCheckAt":"2026-10-29T13:12:40.386Z","isFirstParty":false,"canonicalSlug":"bicycle-gearing-fit-calc-cadence-for-speed-de2d7b53"}