Zenturizer

Calculates the best-fitting Zwift routes to simulate any real-world ride, based on your desired distance and climbing.

Update history (newest first)

Mar 13 2025: Humongous data update! Incorporated 70 recently-added routes, and all route data validated against ZwiftInsider.com.
Jan 14 2024: Handle routes with missing ZwiftInsider pages. New routes added: Watopia Southern Coast expansion (8), Tour of Zwift rebel routes (3), and Innsbruck Continental Qualifier.
Sep 15 2023: Added five Scotland routes and some miscellaneous others.
Apr 09 2022: Fix broken ZwiftInsider route links.
Mar 15 2022: Added two Makuri and five Watopia new routes.
Jan 23 2022: Improve handling of non-loop routes (see "calculation details" below).
Jan 22 2022: Add new checkbox to optionally include/exclude event-only routes.
Jan 19 2022: Convert from CSV backend to database.
Jan 16 2022: Added two more Makuri routes.
Dec 21 2021: Added update history section.
Nov 16 2021: Count number of routes programmagically, rather than hardcoding it.
Sep 21 2021: Added eight new Makuri/Neokyo routes. Also changed route links to open in new browser tab.
Aug 21 2021: Added two more Makuri/Yumezi routes.
Jul 21 2021: Added two more Makuri/Yumezi routes.
May 21 2021: Added Makuri/Yumezi routes. Also fixed json fetching error.
Jul 22 2020: Added Paris and France routes.
May 24 2020: Show an accuracy factor (%) for the top selected routes.
May 21 2020: Allow input/output in imperial units. Added links to course pages. Save units preference. Added tech details section.
May 15 2020: Initial version released.

Calculation details

Estimates take into account route lead-ins (once of course).
It shouldn't matter (much) if you ride the routes in the forward or reverse direction.
Warning! Take the accuracy estimates seriously. On a long ride, a 6% difference in accuracy might mean a lot more distance or climbing than you wanted!
Routes that are not loops only appear if you can accrue enough distance and climbing to complete your ride by the end of the route, since you can't do multiple laps.
Warning! Estimates are based on the overall slope of each route. It doesn't know where the hills are located within each route. So if an estimate tells you to ride a fractional portion of a lap, be aware that depending on that route's specific incline profile you might need to ride a little bit further than indicated in order to match your exact distance and climbing goal.