Home / Compare / Claude Fable 5.1 vs Nemotron 3 Ultra

Claude Fable 5.1 vs Nemotron 3 Ultra

For a typical chat reply (2,000 tokens in, 400 out), Claude Fable 5.1 costs 19× as much as Nemotron 3 Ultra: $40.00 against $2.16 per 1,000 requests at list price on 2026-09-28.

Claude Fable 5.1Nemotron 3 Ultra
Input, per 1M tokens$10.00$0.60
Output, per 1M tokens$50.00$2.40
Context window1M262K
Classification or routing (600 tokens in, 10 out), per 1,000$6.50$0.384
Chat reply (2,000 in, 400 out), per 1,000$40.00$2.16
Retrieval-augmented answer (8,000 in, 500 out), per 1,000$105$6.00
Confidence signalnono
Tool callingyesyes

Which one should carry your traffic?

If Nemotron 3 Ultra answers your requests as well as Claude Fable 5.1, moving that traffic saves 95% on chat-shaped requests. Averages cannot tell you whether it does for your requests. Nemotron 3 Ultra 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 · Nemotron 3 Ultra profile · Measure it on your traffic