Standard Compute
Model Comparison 2026

Claude Opus 4.8 vs GPT-5.5

Claude Opus 4.8
Anthropic · Frontier · Proprietary
$11/1M · 1M ctx
GPT-5.5
OpenAI · Frontier · Proprietary
$13/1M · 1.1M ctx

Community Vote

Pick a winner in each dimension — change your vote anytime.

Output Quality
Correctness and depth of what it produces
Agentic Ability
Tool calls, instruction-following, and multi-step tasks
Speed
Tokens per second and time-to-first-token
Value for $
How much capability you get per dollar
Reliability
Consistent results — fewer refusals, loops, and format breaks

Specs & Pricing, Side by Side

Spec
Opus 4.8
GPT-5.5
Maker
Anthropic
OpenAI
Blended price / 1M
$11
$13
Input / output
$5.00 in · $25 out / 1M tokens
$5.00 in · $30 out / 1M tokens
Context window
1M
1.1M
Open weights
No
No
Tool use
Yes
Yes
Reasoning
Yes
Yes
Output Quality
9.6
9.6
Agentic Ability
9.6
9.5
Speed
7.2
7.0
Value for $
7.5
7.5
Reliability
9.5
9.0

Pricing and capabilities synced from the OpenRouter catalogue. Scores are editorial (0–10).

Verdict: Opus 4.8 or GPT-5.5?

Updated 2026-08-02

Choose Claude Opus 4.8 if you want hard, high-stakes coding and reasoning where quality matters more than cost. Choose GPT-5.5 if you want hard reasoning and coding for teams in the OpenAI ecosystem.

In our editorial scoring, Claude Opus 4.8 leads in 3 of five dimensions (agentic ability, speed and reliability), while GPT-5.5 leads in 0. On price, Claude Opus 4.8 runs about $11 per 1M tokens (blended) and is proprietary; GPT-5.5 is about $13 and proprietary.

Where Opus 4.8 falls short
  • Among the most expensive models per token
  • Slower than lighter models on simple tasks
Full Opus 4.8 breakdown →
Where GPT-5.5 falls short
  • Premium pricing
  • Slower than mini/flash tiers
Full GPT-5.5 breakdown →

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