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Claude Fable 5.1 vs Gemini 4 Argon

Updated Oct 24, 2026. Checked daily.

These are the current #1 and the alternative for Legal & Long Documents.

#1

Claude Fable 5.1

Anthropic

Evidence
Vals LegalBench 88.5% (top 2 of 150+ models)
Cost
Pro is $20/month. Fable draws on usage credits. API is $10 per million input tokens and $50 per million output.
Access
Paid plan
Privacy
Anthropic says Free, Pro, and Max chats are used for training only if you allow it, and you choose at signup. The toggle has been reported as on by default, so check it. Settings, then Privacy. Turn off Help improve Claude.
Pick this if
Pick this when analyzing high-stakes contracts, filings, and long transcripts.

Alternative

Gemini 4 Argon

Google

Evidence
Vals LegalBench 88.3%
Cost
Google AI Pro is $19.99/month. API is $2 per million input tokens until Nov 30, 2026, then $4.
Access
Paid plan
Privacy
Yes for adults. Gemini Apps Activity is on by default, and those chats can be used to improve Google AI. Gemini Apps Activity, turn off Keep Activity. Safety review can still apply.
Pick this if
Pick this when you want a close legal score for less money.

Questions

Which is better for legal & long documents, Claude Fable 5.1 or Gemini 4 Argon?

Claude Fable 5.1 leads legal & long documents on Vals LegalBench. Claude Fable 5.1 scores 88.5 and Gemini 4 Argon scores 88.3 on that signal.

Which is cheaper?

Claude Fable 5.1 costs Pro is $20/month. Fable draws on usage credits. API is $10 per million input tokens and $50 per million output. Gemini 4 Argon costs Google AI Pro is $19.99/month. API is $2 per million input tokens until Nov 30, 2026, then $4. These are the stored prices, not a guess about which plan is cheaper for you.

Which is more private?

Claude Fable 5.1: Anthropic says Free, Pro, and Max chats are used for training only if you allow it, and you choose at signup. The toggle has been reported as on by default, so check it. Gemini 4 Argon: Yes for adults. Gemini Apps Activity is on by default, and those chats can be used to improve Google AI.