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Simon Willison
simonwillison.net
did:plc:kft6lu4trxowqmter2b6vg6z
Notes (and a Pelican) on Claude Sonnet 5 - the new tokenizer makes it ~1.4x more expensive for English, ~1.33x more expensive for Spanish but roughly the same price for Simplified Mandarin https://simonwillison.net/2026/Jun/30/claude-sonnet-5/
2026-06-30T21:25:05.819Z