# Chargaff Rule Calculator

> Chargaff rule calculator: verify A=T and G=C base pairing rules from DNA composition and find missing base percentages. Free, private, runs locally offline.

- **Canonical URL:** https://boringtoolskit.com/chargaff-rule-calculator/
- **Category:** Biology
- **Evidence level:** catalogue
- **Reviewed:** July 26, 2026
- **Last verified:** 2026-10-12
- **Privacy:** Inputs and results stay in this browser unless the page clearly labels an external request.

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