Disclaimer

Last updated: September 2026. Please read this page carefully before using our calculators.

Educational information only

All content on BirdTable — calculators, articles, tables, and examples — is published for general educational purposes. It is not professional advice and is not a substitute for a qualified professional. We are not qualified professional in the relevant fields, and no client or advisory relationship is created by your use of this Site.

Entries describe typical field marks, songs, and feeder behavior for common North American species. Regional variation is real — local guides and eBird-style checklists refine by your area.

Feed birds responsibly: clean feeders regularly, keep cats indoors, and never feed bread or junk food to wild birds.

Accuracy of calculations

We implement well-known, publicly documented formulas (see the methodology section on each calculator page and published field guides and reference literature as applicable). Even correctly implemented formulas produce estimates that depend on your inputs and assumptions. Real-world outcomes vary. Do not rely on a single web tool for a consequential decision.

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Errors and corrections

If you spot an error, please email hello@www.birdtable.org with the inputs you used. Verified corrections are published promptly.