GPT-5.5 Pro vs Claude Opus 4.8

Price & specs

Per 1M tokens, base rates from your credit balance — no usage markup. Prices load live from our catalogue.

When to pick each

GPT-5.5 Pro

Best for the hardest reasoning, agentic and coding tasks. Context up to 1M tokens. GPT-5.5 Pro details →

Claude Opus 4.8

Best for the hardest reasoning, agentic and coding tasks. Context up to 1M tokens. Claude Opus 4.8 details →

Test both with one change

Because Zylo is OpenAI-compatible, comparing them is a one-string change.

for model in ["gpt-5.5-pro", "claude-opus-4.8"]:
    r = client.chat.completions.create(
        model=model,
        messages=[{"role": "user", "content": "Summarize this in one line."}],
    )
    print(model, "->", r.choices[0].message.content)

Frequently asked questions