Who is Jason?
The cat. The format is spelled JSON and is one page over.
September 1, 2026 · 2 minute readJason is a cat
Jason is an orange cat with black stripes near his ears and down his stomach. He looks rightways, and he is on all fours, in every appearance, without exception. He is the mascot of jsontools.me.
He parses nothing. He holds no position on trailing commas. He is here because the format this site is built around is pronounced exactly like a cat's name, and it seemed wasteful not to have the cat.
JSON is a format
If you arrived looking for the thing with the braces, that is JSON — spelled without the second A and pronounced with it. It is a text format for data interchange: six types, one page of grammar, and a parser in every language that has ever shipped one.
It is not a file system, not a storage medium, and not a person. The long version — Douglas Crockford's account of discovering rather than inventing it, the license clause about evil, and why a JSON payload beats an .xlsx for anything a machine has to read — is one page over.
The pronunciation is why this page exists
The 2017 international standard states that JSON is "pronounced /ˈdʒeɪ.sən/, as in 'Jason and The Argonauts'." A standards body wrote that down and shipped it. It is the load-bearing citation for this entire mascot.
Crockford, in 2011, was less invested: "There's a lot of argument about how you pronounce that, but I strictly don't care." The cat has no comment either.