Claude Opus 4.8 vs GPT-5.2

Anthropic · US  |  OpenAI · US · Updated June 2026

Quick verdict

Pick Claude Opus 4.8 for agentic coding and multi-file debugging or long autonomous tasks. Pick GPT-5.2 for strong all-round reasoning or reliable structured output. On a tight budget at scale, GPT-5.2 is the value pick.

Claude Opus 4.8 (Anthropic) and GPT-5.2 (OpenAI) are two of the models people most often weigh against each other in 2026. Claude Opus 4.8 is the agentic-coding and judgment leader — highest SWE-Bench Pro score ever recorded at launch. GPT-5.2 is a capable GPT-5-generation all-rounder, now succeeded by GPT-5.5. 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 4.8GPT-5.2
ProviderAnthropic (US) OpenAI (US)
ReleasedMay 28, 2026 2026
Context window1M (~1,500 pages) 400K (~600 pages)
Price (in/out)$5/$25 per 1M tokens $1.5/$10 per 1M tokens
Open weight?No — API only No — API only
Modalitiestext, image, code text, image, code
SWE-Bench Verified88.6% Not published
MRCR v2 @ 1MNot published Not published

Who wins what

Agentic coding and multi-file debugging

Claude Opus 4.8

A core design strength of Claude Opus 4.8.

Long autonomous tasks

Claude Opus 4.8

A core design strength of Claude Opus 4.8.

Honest uncertainty flagging

Claude Opus 4.8

A core design strength of Claude Opus 4.8.

Strong all-round reasoning

GPT-5.2

A core design strength of GPT-5.2.

Reliable structured output

GPT-5.2

A core design strength of GPT-5.2.

Broad ecosystem and tooling

GPT-5.2

A core design strength of GPT-5.2.

Lowest cost at scale

GPT-5.2

At $1.5/$10 per 1M tokens, it is the cheaper of the two — the gap dominates the bill on high-volume workloads.

Largest single-prompt input

Claude Opus 4.8

Its 1M window is about 2.5× larger, fitting roughly 1,500 pages in one prompt.

Which should you pick?

A cost-sensitive startup shipping high volume

GPT-5.2

At $1.5/$10 per 1M tokens it undercuts Claude Opus 4.8, and on millions of tokens that margin decides the monthly bill.

Someone analysing very long documents or codebases

Claude Opus 4.8

Larger 1M window fits more in one prompt.

Anyone whose priority is agentic coding and multi-file debugging

Claude Opus 4.8

It is specifically built for that.

Anyone whose priority is strong all-round reasoning

GPT-5.2

That is its strongest area.

Claude Opus 4.8: where it fits

The agentic-coding and judgment leader — highest SWE-Bench Pro score ever recorded at launch. Released May 28, 2026 by Anthropic, it is built for agentic coding and multi-file debugging, long autonomous tasks, honest uncertainty flagging, and professional writing and reasoning.

Its trade-offs are real: highest per-token price of the frontier tier, and not the cheapest for high-volume work. At $5 in / $25 out per million tokens, it sits in the premium price band.

GPT-5.2: where it fits

A capable GPT-5-generation all-rounder, now succeeded by GPT-5.5. Released 2026 by OpenAI, it is built for strong all-round reasoning, reliable structured output, broad ecosystem and tooling, and professional workflows.

Its trade-offs: superseded by GPT-5.5, and smaller context than flagships. At $1.5 in / $10 out per million tokens, it sits in the mid price band.

The bottom line for this matchup

Claude Opus 4.8 and GPT-5.2 overlap enough that the right pick depends on your specific job. GPT-5.2 costs less per token; Claude Opus 4.8 holds the larger context; and each leads in its own area — Claude Opus 4.8 for agentic coding and multi-file debugging, GPT-5.2 for strong all-round reasoning. Rather than crowning one, run the same hard task through both once and let the results decide.

Want both Claude Opus 4.8 and GPT-5.2 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 4.8 or GPT-5.2 better for coding?

Public SWE-Bench figures are not available for GPT-5.2, so the honest test is your own repository — run an identical real bug through both. By design, Claude Opus 4.8 leans toward agentic coding and multi-file debugging while GPT-5.2 leans toward strong all-round reasoning, and that positioning usually predicts which feels better on your codebase.

Which is cheaper, Claude Opus 4.8 or GPT-5.2?

GPT-5.2 is cheaper — $5/$25 per 1M tokens vs $1.5/$10 per 1M tokens, roughly 3.3× apart on input.

Which has the bigger context window?

Claude Opus 4.8 — 1M vs 400K, about 2.5× larger. Useful only if the model actually reasons over the full window, which not all do.

Can I use both Claude Opus 4.8 and GPT-5.2 together?

Yes — a multi-model platform like LumiChats gives you Claude Opus 4.8, GPT-5.2 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 4.8 or GPT-5.2?

Claude Opus 4.8 — released May 28, 2026, about 4 months after GPT-5.2.

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.