Climbing Grade API
Rock-climbing grade conversion as an API, computed locally and deterministically — the cross-system grade translations a climber, gym or guidebook app needs when the same route reads differently in every country. The route endpoint takes a roped-climbing grade in any major system — the American Yosemite Decimal System (5.5 to 5.15d), French sport grades (4b to 9c+), the UIAA scale used across Central Europe (IV to XIII-) or the Australian/New Zealand Ewbank numbers (12 to 40) — and returns the equivalents in all of them, so a 5.11a is a French 6c, a UIAA VII+ and an Ewbank 22. The boulder endpoint converts between the American V-scale (VB and V0 to V17) and the French Fontainebleau scale (3 to 9A), so a V5 is Font 6C and a problem graded 7A is about V6. You can pass a grade in any supported system and it finds the row and gives the rest — handy for syncing a tick list across regions or showing a climber a grade they recognise. Everything is computed locally and deterministically, so it is instant and private. Ideal for climbing, bouldering, gym, guidebook and outdoor-sports app developers, tick-list and route-database tools, and training-log software. Pure local computation — no key, no third-party service, instant. Chart equivalents — grades are inherently approximate across systems. Live, nothing stored. 2 conversion endpoints.
api.oanor.com/climbgrade-api