Home / Compare / Claude Fable 5.1 vs Phi 4

Claude Fable 5.1 vs Phi 4

For a typical chat reply (2,000 tokens in, 400 out), Claude Fable 5.1 costs 204× as much as Phi 4: $40.00 against $0.196 per 1,000 requests at list price on 2026-09-28.

Claude Fable 5.1Phi 4
Input, per 1M tokens$10.00$0.07
Output, per 1M tokens$50.00$0.14
Context window1M16K
Classification or routing (600 tokens in, 10 out), per 1,000$6.50$0.0434
Chat reply (2,000 in, 400 out), per 1,000$40.00$0.196
Retrieval-augmented answer (8,000 in, 500 out), per 1,000$105$0.63
Confidence signalnono
Tool callingyesno

Which one should carry your traffic?

If Phi 4 answers your requests as well as Claude Fable 5.1, moving that traffic saves 100% on chat-shaped requests. Averages cannot tell you whether it does for your requests. Phi 4 does not expose a confidence signal through OpenRouter, so Gimbix would test it as a full replacement rather than a first answer.

Claude Fable 5.1 profile · Phi 4 profile · Measure it on your traffic