Convert ZWO to TCX

Turn a Zwift ZWO workout into a TCX (Training Center XML) file — the format most training platforms accept for import. Use the free, in-browser Kaiord Editor (no account, no upload), or the CLI and TypeScript SDK. Conversions go through Kaiord's canonical KRD format and stay within round-trip tolerances (time ±1 s, cadence ±1 rpm).

Three ways to convert

1. Editor (drag & drop)

Open kaiord.com/editor, drop your .zwo file, choose TCX as the export format, and download workout.tcx.

2. CLI

pnpm add -g @kaiord/cli
kaiord convert -i workout.zwo -o workout.tcx

3. SDK

import { fromText, toText } from "@kaiord/core";
import { zwiftReader } from "@kaiord/zwo";
import { tcxWriter } from "@kaiord/tcx";
import { readFile, writeFile } from "node:fs/promises";

const zwo = await readFile("workout.zwo", "utf-8");
const krd = await fromText(zwo, zwiftReader);
const tcx = await toText(krd, tcxWriter);
await writeFile("workout.tcx", tcx);

What survives the conversion

Data	ZWO (Zwift)	TCX	Result
Step order & names	blocks	<Step> / <Name>	Preserved
Time durations	Duration seconds	Time_t seconds	Preserved (±1 s)
Power targets	% FTP (Power fraction)	—	Dropped — TCX workouts have no power target
Ramps	Warmup / Cooldown / Ramp	untargeted steps	Duration preserved; the power ramp is dropped
Cadence targets	limited	Cadence_t	Preserved when present (±1 rpm)
Free-ride segments	FreeRide	untargeted step	Preserved as a step without a target
Repeats / intervals	IntervalsT	Repeat_t	Preserved

Gotchas

My power targets disappeared. The TCX workout schema (Garmin Training Center) defines heart-rate, speed, and cadence targets only — there is no power target. Zwift workouts are power-based (% FTP), so the power targets have nowhere to land and are dropped; the step structure and durations remain. To keep power, convert to FIT or Garmin Connect instead.

So why convert to TCX at all? TCX is a widely accepted interchange format — TrainingPeaks, Strava, and Garmin Connect all import it — so it is useful when you want the workout's structure (steps, durations, intervals) on a platform that reads TCX but cannot read ZWO. Just expect the power targets not to come along.

Cadence. If your ZWO carries cadence targets, they map to TCX Cadence_t targets. Most Zwift workouts are pure power, so this is often empty.

Related

• Convert TCX to ZWO — the reverse direction
• Convert ZWO to FIT — keep power targets
• ZWO format · TCX format
• All converters