The reference desk — standardized codes, filed & searchableN° 2,372 entries · 11 collections ·
DirectoryCodes
The directory of the world’s codes

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Ask anything about the codes filed here — “Which country uses +358?”, “What's the difference between 301 and 308?”, “Which airport is HND?” — and get an answer grounded in the directory's own 2,372-entry ledger, with links back to the source pages.

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