Claude Opus 5 vs GPT-6 Sol

Anthropic · US  |  OpenAI · US · Updated June 2026

Quick verdict

Pick Claude Opus 5 for frontier reasoning at lower cost per task — anthropic reports it more than doubling opus 4.8 on frontier-bench v0.1 or agentic coding — within 0.5% of fable 5's peak cursorbench 3.2 score at half the cost per task (anthropic's figures). Pick GPT-6 Sol for openai's everyday-work tier below gpt-6 astra, built with the same methods that improved astra's professional work, factuality, coding, computer use, and alignment or openai says it makes about half as many mistakes as gpt-5.6 sol. On a tight budget at scale, GPT-6 Sol is the value pick.

Claude Opus 5 (Anthropic) and GPT-6 Sol (OpenAI) are two of the models people most often weigh against each other in 2026. Claude Opus 5 is anthropic's July 2026 flagship at $5/$25 with a 1M window and an effort dial — near-frontier quality pitched on cost per task, not raw peak. GPT-6 Sol is openAI's September 22, 2026 mid-tier update — Astra-derived improvements at half the GPT-5.6 Sol price, $2/$10 per million tokens. They diverge most on price and context window — each quantified below from the models' real specs.

Key differences at a glance

Side-by-side specs

SpecClaude Opus 5GPT-6 Sol
ProviderAnthropic (US) OpenAI (US)
ReleasedJuly 24, 2026 September 22, 2026
Context window1M (~1,500 pages) 1.05M tokens (~1,575 pages)
Price (in/out)$5/$25 per 1M tokens $2/$10 per 1M tokens
Open weight?No — API only No — API only
Modalitiestext, image, code text, image
SWE-Bench VerifiedNot published Not published
MRCR v2 @ 1MNot published Not published

Who wins what

Frontier reasoning at lower cost per task — Anthropic reports it more than doubling Opus 4.8 on Frontier-Bench v0.1

Claude Opus 5

GPT-6 Sol is comparatively weak here — more reasoning capability than sibling GPT-6 Luna, but still positioned below flagship GPT-6 Astra

Agentic coding — within 0.5% of Fable 5's peak CursorBench 3.2 score at half the cost per task (Anthropic's figures)

Claude Opus 5

Claude Opus 5 lists agentic coding — within 0.5% of Fable 5's peak CursorBench 3.2 score at half the cost per task (Anthropic's figures) among its strengths; GPT-6 Sol does not.

Computer use — surpasses Fable 5's best OSWorld 2.0 result at just over a third of the cost

Claude Opus 5

Claude Opus 5 lists computer use — surpasses Fable 5's best OSWorld 2.0 result at just over a third of the cost among its strengths; GPT-6 Sol does not.

OpenAI's everyday-work tier below GPT-6 Astra, built with the same methods that improved Astra's professional work, factuality, coding, computer use, and alignment

GPT-6 Sol

Claude Opus 5 is comparatively weak here — no published SWE-Bench Verified score, so head-to-head coding comparisons rely on Anthropic's own benchmark suite

OpenAI says it makes about half as many mistakes as GPT-5.6 Sol

GPT-6 Sol

OpenAI's September 22, 2026 mid-tier update — Astra-derived improvements at half the GPT-5.6 Sol price, $2/$10 per million tokens — and it runs cheaper at $2/$10 per 1M tokens.

Priced at half of the GPT-5.6 Sol/Luna generation's rates ($2/$10 vs GPT-5.6 Sol's $5/$30)

GPT-6 Sol

At $2/$10 per 1M tokens it undercuts Claude Opus 5 ($5/$25 per 1M tokens), and that gap compounds at volume.

Lowest cost at scale

GPT-6 Sol

At $2/$10 per 1M tokens, it is the cheaper of the two — the gap dominates the bill on high-volume workloads.

Which should you pick?

A cost-sensitive startup shipping high volume

GPT-6 Sol

At $2/$10 per 1M tokens it undercuts Claude Opus 5, and on millions of tokens that margin decides the monthly bill.

Someone analysing very long documents or codebases

GPT-6 Sol

Larger 1.05M tokens window fits more in one prompt.

Anyone whose priority is frontier reasoning at lower cost per task — anthropic reports it more than doubling opus 4.8 on frontier-bench v0.1

Claude Opus 5

It is specifically built for that.

Anyone whose priority is openai's everyday-work tier below gpt-6 astra, built with the same methods that improved astra's professional work, factuality, coding, computer use, and alignment

GPT-6 Sol

That is its strongest area.

Claude Opus 5: where it fits

Anthropic's July 2026 flagship at $5/$25 with a 1M window and an effort dial — near-frontier quality pitched on cost per task, not raw peak. Released July 24, 2026 by Anthropic, it is built for frontier reasoning at lower cost per task — Anthropic reports it more than doubling Opus 4.8 on Frontier-Bench v0.1, agentic coding — within 0.5% of Fable 5's peak CursorBench 3.2 score at half the cost per task (Anthropic's figures), computer use — surpasses Fable 5's best OSWorld 2.0 result at just over a third of the cost, and a native effort setting (low, medium, high, xhigh, max) that trades token cost against capability on a single model.

Its trade-offs are real: behind Mythos 5 on cybersecurity exploitation and biology research, by Anthropic's own account, all launch benchmarks are Anthropic-reported and not yet independently reproduced, no published SWE-Bench Verified score, so head-to-head coding comparisons rely on Anthropic's own benchmark suite, and fast mode's throughput costs double the base price ($10/$50 per 1M). At $5 in / $25 out per million tokens, it sits in the premium price band.

GPT-6 Sol: where it fits

OpenAI's September 22, 2026 mid-tier update — Astra-derived improvements at half the GPT-5.6 Sol price, $2/$10 per million tokens. Released September 22, 2026 by OpenAI, it is built for openAI's everyday-work tier below GPT-6 Astra, built with the same methods that improved Astra's professional work, factuality, coding, computer use, and alignment, openAI says it makes about half as many mistakes as GPT-5.6 Sol, priced at half of the GPT-5.6 Sol/Luna generation's rates ($2/$10 vs GPT-5.6 Sol's $5/$30), and 1.05M-token context window, input capped at 922K.

Its trade-offs: more reasoning capability than sibling GPT-6 Luna, but still positioned below flagship GPT-6 Astra, and cache-read pricing ($0.20/MTok) still costlier than Luna's ($0.01/MTok) for high-cache workloads. At $2 in / $10 out per million tokens, it sits in the mid price band.

The bottom line for this matchup

Claude Opus 5 and GPT-6 Sol overlap enough that the right pick depends on your specific job. GPT-6 Sol costs less per token; GPT-6 Sol holds the larger context; and each leads in its own area — Claude Opus 5 for frontier reasoning at lower cost per task — anthropic reports it more than doubling opus 4.8 on frontier-bench v0.1, GPT-6 Sol for openai's everyday-work tier below gpt-6 astra, built with the same methods that improved astra's professional work, factuality, coding, computer use, and alignment. Rather than crowning one, run the same hard task through both once and let the results decide.

Want both Claude Opus 5 and GPT-6 Sol without two subscriptions? LumiChats gives you these plus 40+ models under one ₹69/day pass (about $1/day) — draft with one, cross-check with the other.

See pricing

Frequently asked questions

Is Claude Opus 5 or GPT-6 Sol better for coding?

Public SWE-Bench figures are not available for either model, so the honest test is your own repository — run an identical real bug through both. By design, Claude Opus 5 leans toward frontier reasoning at lower cost per task — anthropic reports it more than doubling opus 4.8 on frontier-bench v0.1 while GPT-6 Sol leans toward openai's everyday-work tier below gpt-6 astra, built with the same methods that improved astra's professional work, factuality, coding, computer use, and alignment, and that positioning usually predicts which feels better on your codebase.

Which is cheaper, Claude Opus 5 or GPT-6 Sol?

GPT-6 Sol is cheaper — $5/$25 per 1M tokens vs $2/$10 per 1M tokens, roughly 2.5× apart on input.

Which has the bigger context window?

Effectively neither — 1M vs 1.05M tokens is a difference of a few percent. Remember advertised ≠ usable: recall typically degrades before the ceiling.

Can I use both Claude Opus 5 and GPT-6 Sol together?

Yes — a multi-model platform like LumiChats gives you Claude Opus 5, GPT-6 Sol and 40+ others under one ₹69/day pass (about $1/day), so you can draft with one and cross-check with the other instead of buying two subscriptions.

Which is newer, Claude Opus 5 or GPT-6 Sol?

GPT-6 Sol — released September 22, 2026, about 2 months after Claude Opus 5.

Related comparisons

Specifications and benchmarks reflect publicly reported figures as of June 2026 and may change as providers release updates. Always verify on your own workload.