Claude Sonnet 5 (Medium) vs GPT-5.5 Instant (June 2026)
Which is better for the money: Claude Sonnet 5 (Medium) by Anthropic or GPT-5.5 Instant (June 2026) by OpenAI? Intelligence, total benchmark cost, and end-to-end time from Artificial Analysis & other sources, snapshot 2026-10-26.
Trade-off
Verdict
Depends on your budget
Claude Sonnet 5 (Medium) scores 2.1 points higher (28.1 vs 26.0) but costs 1.0× as much to run the benchmark ($1218 vs $1184; both premium class). Pick Claude Sonnet 5 (Medium) when the extra intelligence is worth the premium, otherwise GPT-5.5 Instant (June 2026).
| Metric | Claude Sonnet 5 (Medium) | GPT-5.5 Instant (June 2026) | Difference |
|---|---|---|---|
| Intelligence (higher is better) | 28.1 | 26.0 | −7.5% GPT-5.5 Instant (June… is 7.5% less intelligent |
| Total AA cost (lower is better) | $1,218.17 | $1,184.34 | −2.8% GPT-5.5 Instant (June… is 2.8% cheaper |
| End-to-end time (lower is better) | 9.09s | 16.68s | +83.5% GPT-5.5 Instant (June… is 83.5% slower |
| Price per 1M tokens (in / out) | $2.00 / $10.0 | $5.00 / $30.0 | |
| Input modalities | Text, Image | Text, Image |
GPT-5.5 Instant (June 2026) vs Claude Sonnet 5 (Medium): 7.5% less intelligence, 2.8% less cost to run the AA benchmark, and 83.5% slower end-to-end.
Today's Pareto frontier
Against the frontier
- Claude Sonnet 5 (Medium) is off the frontier: at the same or lower cost, GPT-6.1 Sol (Max) scores 51.80 for $1082.
- GPT-5.5 Instant (June 2026) is off the frontier: at the same or lower cost, GPT-6.1 Sol (Max) scores 51.80 for $1082.
Claude Sonnet 5 (Medium)GPT-5.5 Instant (June 2026)Today's Pareto frontierEvery other model
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Accept: text/markdown or ?format=md returns this page as Markdown. JSON: /api/v1/compare/claude-sonnet-5-medium/gpt-5-5-instant-06-26 · Markdown: /api/v1/compare/claude-sonnet-5-medium/gpt-5-5-instant-06-26?format=md · llms.txt · agent skill