Fennel Bulb vs Onion
A side-by-side guide to substituting Onion for Fennel Bulb (or vice versa).
Use 0.7 lb of Onion for every 1 lb of Fennel Bulb.
Side-by-side
Onion
Conversion: Use 70% as much (0.7 lb per 1 lb)
Tags: budget
Notes: Milder than fennel, no anise notes. Use 30% less to avoid overpowering; best in cooked applications.
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Milder than fennel, no anise notes. Use 30% less to avoid overpowering; best in cooked applications. The conversion is use 70% as much (0.7 lb per 1 lb).
Common questions
Yes — Milder than fennel, no anise notes. Use 30% less to avoid overpowering; best in cooked applications. Ratio: Use 70% as much (0.7 lb per 1 lb).
Use 70% as much (0.7 lb per 1 lb). For other quantities, use the SubSwap calculator.
They are similar in most uses, but Milder than fennel, no anise notes..
Onion is one of the options SubSwap lists for Fennel Bulb. The 'best' choice depends on your recipe — see the full list of Fennel Bulb substitutes.
Looking for more Fennel Bulb substitutes beyond Onion?
See all Fennel Bulb swaps →