Did you ever need to look up a number, only to find yourself spending much more time than you wanted on the Internet or flipping through textbooks - all without much success?

Well, it didn’t happen only to you. It is often surprising how difficult it can be to find concrete numbers, even for properties that have been measured numerous times. Inspired by BioNumbers, To help solve this for one and all, IsoNumbers (the database of key stable isotopes numbers in environmental sciences) was created. Along with the numbers, you'll find the relevant references to the original literature, useful comments, and related numbers.

We urge contributors to read the "Resources" section before submitting an isotopic number!