Claude Opus 4.7 vs GPT-5 Mini for legal writing: which is better in 2026?

A head-to-head look at Claude Opus 4.7 and GPT-5 Mini for legal writing. Benchmarks via artificialanalysis.ai, pricing as of May 2026. Compare AI models like these inside Admix.

Quick verdict

For legal writing in May 2026, Claude Opus 4.7 edges out GPT-5 Mini on the contextWindow metric. Most reliable tone and citation behavior for legal drafts.

Side-by-side specs

Spec	Claude	GPT-5 Mini
Intelligence index	76.9	64.5
Coding index	82.3	61.0
Context window	1M tokens	200K tokens
Speed (tok/s)	88	220
Input $/M	$15.00	$0.25
Output $/M	$75.00	$1.00
Released	Apr 23, 2026	Sep 10, 2025

How they handle legal writing

Claude Opus 4.7: Most reliable tone and citation behavior for legal drafts.

GPT-5 Mini: Excellent quality-to-price ratio. The main caveat is behind flagships on hard reasoning.

Cost per 1,000 queries

Assuming 1,500 input and 800 output tokens per query:

Claude Opus 4.7: $82.50 per 1,000 queries
GPT-5 Mini: $1.18 per 1,000 queries

Verdict by sub-task

Best raw quality on legal writing:
Best price: GPT-5 Mini
Longest context: Claude Opus 4.7
Fastest: GPT-5 Mini

FAQ

Is Claude Opus 4.7 better than GPT-5 Mini for legal writing?

On May 2026 benchmarks (artificialanalysis.ai), Claude Opus 4.7 ranks higher than GPT-5 Mini for legal writing on the contextWindow metric. The gap is small enough that the choice often comes down to price, context length, and tone.

Which is cheaper, Claude Opus 4.7 or GPT-5 Mini?

Claude Opus 4.7 costs $15.00 input and $75.00 output per million tokens. GPT-5 Mini costs $0.25 input and $1.00 output per million tokens.

Can I use both Claude and GPT-5 Mini in one app?

Yes. Admix is a multi model AI chat aggregator that lets you run Claude Opus 4.7 and GPT-5 Mini side by side under one subscription.

Sources

Benchmarks from artificialanalysis.ai (May 2026).

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