The InChIKeyStep 17 of 17 of the InChI walkthrough. The InChIKey is a fixed-length hash built for search boxes and database columns. The InChI is cut in two — a skeleton part and everything else — each is hashed with SHA-256, and the leading bits are written in base 26. Every step below can be followed by hand except the SHA-256 itself, which is shown for you.It opens on CN1C=NC2=C1C(=O)N(C)C(=O)N2C, drawn live, so the layer under discussion changes as you change the structure.Convert a structure to its InChI and InChIKey and back, convert a whole CSV, XLSX or SDF file, learn how the identifier is derived, and practise writing its layers. The InChI engine is WebAssembly running in your browser, so the tool needs JavaScript — and nothing you open ever leaves your machine.

Convert — a structure in, an InChI out

Batch — a whole CSV, XLSX or SDF file

Tutorial — how an InChI is derived

Exercises — write the layers yourself

Cheatsheet — every layer in a table

Tests — the IUPAC regression corpora

Download — take the engine away

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