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pH Calculator
Find pH, pOH and concentrations for strong and weak acids and bases, and buffers with the Henderson-Hasselbalch equation.
Free, no uploads, no sign-up. Runs 100% in your browser.
How pH Calculator works
All maths runs in your browser, instantly, with no account. Weak acids are solved with the exact quadratic, and very dilute solutions include water itself.
Input: Numbers. Output: Text.
How to use pH Calculator
- Pick a mode.
- Type the concentration and Ka or pKa.
- Read pH on the colour scale.
Tips
- Exact fractions are used where rounding would give wrong answers.
- Every tool works offline once the page has loaded.
pH Calculator FAQ
- Are my files uploaded?
- No. This tool runs entirely in your browser tab. Files are read from your disk into memory and the result is generated locally.
- Is it free? Are there limits or watermarks?
- Free and open source (MIT). There are no file-size caps, daily quotas, accounts or watermarks.
- Does it work offline?
- Yes, once the page (and any engine it needs) has loaded, it keeps working without a connection thanks to the service worker cache.
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