TCX is Garmin's training format: a GPS track with heart rate, cadence and lap structure wrapped around it. FileSorcery reads it and converts out. Writing one is deliberately not offered, because a schema-valid TCX needs activity timestamps that a converted file cannot honestly invent.
Every conversion below runs in this page, on your own machine. Nothing is uploaded, there is no queue, and there is no account to make. Pick a target format, or just drop a TCX file above and choose afterwards.