InChI Resolver

InChI Resolver

Working Group Chair:  Markus Sitzmann

Is it possible to recalculate the InChI out of an InChIKey? No! The InChIKey is the hashed representation of its InChI. The hashing makes it impossible to go backwards from the InChIKey to the original InChI. To find a solution the “Resolver Protocol” project was started.

The idea is to use publicly accessible databases that store InChIs and their related InChIKeys to resolve a key into information. This includes not only the original structure but also additional data, references or publications linked to the key. The databases may be spread all over the Internet.

The goal of the resolver is run a search for a specific InChIKey over all available database to get the related InChI being found. The technique developed in this project can not only be used to resolve InChIKeys, it is supposed to become a general tool for searches over distributed database systems.

The InChI Resolver Protocol is a common API protocol which allows any InChI Resolver instance to be findable and browsable for an (automated) client system in a systematic, predefined manner.  It will also allow fort the implementation of a network of federated InChI Resolvers.

More information can be found here.


  • web resources providing data & information based on InChI become findable & interlinked on the web
  • their content is accessible in a generic way
  • (long-term) an autonomous client can find and collect information based in InChI

Working Group Members