Download Versions of the InChI Standard

InChI Standard – Download for all versions

Current version

InChI version 1.06 for Standard and Non-Standard InChI/InChIKey (15 December 2020) it includes several additions and modifications to previous versions; it is a combination of a “bugfix release” and “feature release”.

  • INCHI-1-SRC.zip – InChI Software source codes. This file/directory also contains examples of InChI API usage.

Previous Versions

Download InChI software version 1.05 for InChI/InChIKey (27 January 2017)

This package contains InChI Software version 1.05 (January 2017) final release.

  • support for chemical element numbers 113-118 was newly added;
  • experimental support of InChI/InChIKey for simple regular single-strand polymers was implemented;
  • experimental support of large molecules containing up to 32767 atoms was added;
  • ability to read necessary for large molecules input files in Molfile V3000 format was added;
  • provisional support for extended features of Molfile V3000 was added;
  • InChI API Library was significantly updated; in particular, a novel API procedure for direct
    conversion of Molfile input to InChI has been added; a whole new set of API procedures for both low and high-level operations (InChI extensible interface, IXA) has been added;
  • the source code was significantly modified in order to ensure multi-thread execution safety of
    the InChI Library; several minor bugfixes/changes were made and several convenience options
    were added to the inchi-1 executable.

Download InChI software version 1.04 for Standard and Non-Standard InChI/InChIKey (1 September 2011)

This version now supports the chemical elements up to 112, copernicium (the last one which is currently recognized by IUPAC; support for elements 105-112 is newly added). The inchi-1 executable (both Windows and Linux versions) now allows the processing of multiple input files in a single run (common file name wildcards are recognized). In addition version 1.04 also fixes a number of minor bugs.

  • INCHI-1-DOC.zip – contains documentation related to InChI/InChIKey identifiers v. 1 and InChI software v. 1.04 (September 2011).
  • INCHI-1-BIN.zip – contains stand-alone executables for generating the InChI/InChIKey (Windows and Linux).
  • INCHI-1-API.zip – contains code, VC++ projects and gcc makefiles of command-line program inchi-1, as well as of InChI generation library (plus sample applications which use the Library).
  • INCHI-1-TEST.zip – contains the files representing various chemical structures and a simple test suite for InChI/InChIKey software.
    IUPAC / InChI Trust Licence No. 1.0 for the International Chemical Identifier (InChI) Software version 1.04: PDF Format / DOC Format

Each zip should be unpacked into a separate directory. For the details, see ‘RelNotes.pdf’ document in INCHI-1-DOC and the ‘readme.txt’ files in the respective directories.

Documentation for InChI software v. 1.04 (September 2011)

These are individual InChI software v. 1.04 documentation files from the INCHI-1-DOC.ZIP file for rapid access:

 InChI software version 1.03 Source Code Documentation (March 2011)

The InChI Source Code Documentation provided by the InChI Trust:

InChI software version 1.03) for Standard and Non-Standard InChI/InChIKey (June 2010)

  • INCHI-1-DOC.zip – contains documentation related to InChI/InChIKey identifiers v. 1 and InChI software v. 1.03 (2010).
  • INCHI-1-BIN.zip– contains stand-alone executables for generating the InChI/InChIKey (Windows and Linux).
  • INCHI-1-API.zip – contains code, VC++ projects and gcc makefiles of command-line program inchi-1, as well as of InChI generation library (plus sample applications which use the Library).
  • INCHI-1-TEST.zip – contains the files representing various chemical structures and simple test suite for InChI/InChIKey software.
  • LICENSE.PDF – copy of GNU LGPL licence [pdf file]

Each zip should be unpacked into a separate directory. For the details, see ‘RelNotes.pdf’ document in INCHI-1-DOC and the ‘readme.txt’ files in the respective directories.

InChI software version 1.02 for Standard InChI/InChIKey

InChI software version 1.02beta) September 2007

  • inchi102b.zip – source code and Application Program Interface (API), stand-alone executable (cInChI), description of new features, with examples of using new functionality copy of GNU LGPL licence

InChI software version 1.01 August 2006

  • InChI-1.zip – InChI version 1 (software version 1.01) documentation, and Windows and Linux (i386) executable programs
  • InChI-1-API.zip – InChI version 1 (software version 1.01) source code and Application Program Interface (API)
  • InChI-1-validation.zip – InChI validation protocol
  • Whats_New.pdf – What’s new in InChI software version 1.01