Seafood

Vegan alternative to fish sauce: the best substitutes

Everything you need to replace fish sauce with a plant-based substitute — which one to use, the exact ratio, and the mistakes that ruin the result.

Short answer

Soy sauce + lime + a pinch of sugar is the best all-round replacement for fish sauceeveryday substitute. 1:1.

Key takeaways

  • Best all-round swap: Soy sauce + lime + a pinch of sugar (everyday substitute).
  • Ratio: 1:1.
  • Pro tip: A strip of kombu simmered in soy sauce for 10 minutes gives the marine note most swaps miss.
  • 3 tested vegan alternatives to fish sauce in total.

Why fish sauce isn't vegan

Fermented anchovies.

Best vegan substitutes

SubstituteBest for
Soy sauce + lime + a pinch of sugarEveryday substitute
Vegan fish sauce (seaweed-fermented)Closest match for Thai and Viet food
Miso + kombu brothDeep umami without salt overload

How to substitute fish sauce, step by step

  1. 1

    Pick the right substitute for the job

    For most recipes use Soy sauce + lime + a pinch of sugar — everyday substitute. If you need a different texture, Vegan fish sauce (seaweed-fermented) works for closest match for thai and viet food.

  2. 2

    Measure using the correct ratio

    1:1. Weigh rather than eyeball it — small errors show up much faster when replacing fish sauce.

  3. 3

    Adjust the method

    A strip of kombu simmered in soy sauce for 10 minutes gives the marine note most swaps miss.

  4. 4

    Taste and correct

    Plant swaps are usually a little less salty and less rich than fish sauce. Season at the end and add acid (lemon, vinegar) or umami (miso, nutritional yeast) if the dish tastes flat.

Mistakes to avoid

  • Swapping by volume when the recipe measures fish sauce by weight — check the ratio above first.
  • Using a sweetened or flavoured version in a savoury recipe.
  • Ignoring the method change: A strip of kombu simmered in soy sauce for 10 minutes gives the marine note most swaps miss.
  • Assuming every packaged product labelled "plant-based" is vegan — some still contain milk powder, honey or egg. Scan the barcode to be sure.

Conversion ratio

1:1.

Pro tip

A strip of kombu simmered in soy sauce for 10 minutes gives the marine note most swaps miss.

Frequently asked questions

What is the best vegan alternative to fish sauce?
Soy sauce + lime + a pinch of sugar is the closest all-round swap — everyday substitute. 1:1.
Why isn't fish sauce vegan?
Fermented anchovies.
How much do I use instead of fish sauce?
1:1.
Any tips for getting it right?
A strip of kombu simmered in soy sauce for 10 minutes gives the marine note most swaps miss.

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