pH Buffer Calculator · est. 2020
Calculator for pH buffers
As ever, there are no ads, no subscriptions, no login.
This redesign changes how the page looks and works — not the thermodynamics underneath. The calculations and recipes are exactly what they've always been, just delivered more cleanly.
Design a buffer
About this tool
The software:
- Provides a recipe for a range of monoprotic buffers used in biological systems
- Makes corrections for the temperature at which the buffer will be used
- Makes Debye-Hückel corrections for the effect of ionic strength on pKa
- Describes two ways (titration or by accurate weight) for preparation of the recipe
Choose the buffer species you want to use, and enter parameters for volume, pH, and concentration of buffer species. Then include the option to modify the ionic strength by addition of neutral salt. Finally, enter the temperature at which you'll use the buffer, and the temperature at which you'll make it up (these are often not the same). The ‘Recipe’ button will then open a new window with a recipe that you can print, or copy into a lab notebook.
A gentle request
This is a bit embarrassing.
In retirement, I now incur costs to maintain this site. Access will always be free, but if you use the calculator a lot, might you consider making a small donation, most easily through PayPal (stokesay at outlook.com), to help offset the costs of web authoring, domain registration and hosting?
At well over 1.3 million users, it would be appreciated. Many thanks, Rob.
Acknowledgments
Thanks to the following for generous donations to keep this site going. There are three major donors:
Professor Uenal Coskun, Dresden, who made a personal donation to keep the site going for a year.
Dr Jennie Kunitake, Pfizer, USA, who also made a personal donation to keep the site going for a year.
The Analytical Chemistry Trust Fund of the Royal Society of Chemistry, who awarded a grant to ensure the site will be maintained until at least 2030.
I also want to thank:
David Finger
Eyad Naser
Thomas Goyne
Jakob Farnham
Finally, everyone who received the Zwitter card game made a small donation to keeping this web site going — too many to list, unfortunately, but thank you all.
(image to add)
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The original version of the software was written to support a book. To be honest, it doesn't really sell any more, and I'm trying to get the publishers to give me back copyright, so I can release an e-book for free.
Finally, huge thanks to Blaž Janežič who has been enormously helpful in proof reading the site.
You may have arrived here via the University of Liverpool. This route may not be stable. Please make a note of, and change any shortcuts, to: http://phbuffers.org/BuffferCalc/Buffer.html