GPT-5.5 vs Claude Opus 4.8
Side-by-side comparison of API pricing, specs, benchmarks, and capabilities
|
by OpenAI
|
by Anthropic
|
|
|---|---|---|
| Overview | ||
| Status | Current flagship | Current flagship |
| Released | Nov 15, 2025 | May 28, 2026 |
| Pricing per million tokens | ||
| Input | $5.00/Mtok | $5.00/Mtok |
| Output | $30.00/Mtok | $25.00/Mtok |
| Blended avg | $17.50/Mtok | $15.00/Mtok |
| Cached input | $0.500/Mtok | $0.500/Mtok |
| Specifications | ||
| Context window | 270K tokens | 200K tokens |
| Parameters | Proprietary | Proprietary |
| Speed (TPS) | — | — |
| Modalities | ||
| Input |
textimageaudio
|
textimage
|
| Benchmarks from Vellum LLM Leaderboard | ||
| Avg benchmark score | 64 | 80 |
| Perf / dollar | 3.7 | 5.3 |
| GPQA Diamond | — | 93.6 |
| SWE-Bench | — | 88.6 |
| Providers | ||
| Available from |
OpenAI — $5.00/$30.00/Mtok
|
Anthropic — $5.00/$25.00/Mtok
|
Cost at scale — 1M tokens (50/50 input/output)
| Volume | GPT-5.5 | Claude Opus 4.8 | Savings |
|---|---|---|---|
| 1M tokens | $17.5 | $15 | $2.5 (14.3%) |
| 10M tokens | $175 | $150 | $25 (14.3%) |
| 100M tokens | $1750 | $1500 | $250 (14.3%) |
| 1000M tokens | $17500 | $15000 | $2500 (14.3%) |
Summary
GPT-5.5 by OpenAI costs $5.00/Mtok input and $30.00/Mtok output, with a 270K-token context window. It supports text, image, audio input.
Claude Opus 4.8 by Anthropic costs $5.00/Mtok input and $25.00/Mtok output, with a 200K-token context window. It supports text, image input.
On a blended cost basis, Claude Opus 4.8 is 16.7% cheaper than GPT-5.5.
On benchmarks, Claude Opus 4.8 scores higher (80 vs 64) on average. In terms of value, Claude Opus 4.8 has better performance per dollar (5.3 vs 3.7).
Note: Pricing is per million tokens. Actual costs vary with usage patterns, prompt caching, and batch discounts. Always verify against official provider pricing pages.