Did you ever need to look up a number like the volume of a cell or the cellular concentration of ATP, 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 biological numbers, even for properties that have been measured numerous times. To help solve this for one and all, BioNumbers (the database of key numbers in molecular biology) was created. Along with the numbers, you'll find the relevant references to the original literature, useful comments, and related numbers.

Though we have made an honest first try at simplifying the process of finding useful biological numbers, there is still much work to be done. A key challenge is filling in the large number of missing items. Please email us more useful references . Another challenge involves setting up a reliable and discriminating search engine which on a first try yields the numbers a user is actually interested in finding.

-> To cite BioNumbers please refer to: Milo et al. Nucl. Acids Res. (2010) 38: D750-D753. When using a specific entry from the database it is highly recommended that you also specify the BioNumbers 6 digit ID, e.g. "BNID 100986, Milo et al 2010".