Onion vs Leek

A side-by-side guide to substituting Leek for Onion (or vice versa).

Quick answer

Leek works as a 1:1 swap for Onion in most recipes.

Side-by-side

Onion

Base unit: cup

Read the full guide: Onion

Leek

Conversion: 1:1 substitution (use the same amount)

Tags: common

Notes: Leeks are milder and slightly sweeter than onions; use equal volumes but use the white and light green parts only, and clean thoroughly as they trap soil between layers.

Read the full guide: Leek

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When to use Leek instead of Onion

Leeks are milder and slightly sweeter than onions; use equal volumes but use the white and light green parts only, and clean thoroughly as they trap soil between layers. The conversion is 1:1 substitution (use the same amount).

Common questions

Can I substitute Leek for Onion?

Yes — Leeks are milder and slightly sweeter than onions; use equal volumes but use the white and light green parts only, and clean thoroughly as they trap soil between layers. Ratio: 1:1 substitution (use the same amount).

What's the conversion ratio for Onion to Leek?

1:1 substitution (use the same amount). For other quantities, use the SubSwap calculator.

Are Onion and Leek interchangeable?

They are similar in most uses, but Leeks are milder and slightly sweeter than onions; use equal volumes but use the white and light green parts only, and clean thoroughly as they trap soil between layers..

Is Leek a better substitute than other options for Onion?

Leek is one of the options SubSwap lists for Onion. The 'best' choice depends on your recipe — see the full list of Onion substitutes.

Looking for more Onion substitutes beyond Leek?

See all Onion swaps →

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