Choose your substitute based on the kind of horseradish bite your recipe needs: sharp/nasal (wasabi), tangy bite (Dijon), or concentrated punch (mustard powder + vinegar).
Swap using the table ratio (e.g., 1:1) and mix thoroughly so the heat disperses evenly.
If the substitute is milder than horseradish (most mustards), boost tang with 1–2 teaspoon lemon juice or vinegar per 1 tablespoon swap.
If it’s too intense (wasabi or mustard paste), reduce the amount by ½ and extend with a neutral binder like mayo, sour cream, or a splash of water.
Taste after 5 minutes; some mustard-based swaps need a short rest to fully bloom.