I spent an afternoon researching TDEE calculators. Here is what I found:

MacroFactor: $71.99/year. And you need to log every meal for 3 weeks before it gives you a TDEE.

MyFitnessPal Premium: $79.99/year. TDEE is buried in settings.

Cronometer Gold: $59.99/year. Single formula, no Katch-McArdle.

FreeTDEE (freetdee.com): Free. Instant. 6+ formulas. No account.