Which is cheaper, Claude Opus 4.8 or GPT-5.5?

Claude Opus 4.8 is slightly cheaper than GPT-5.5 — identical input pricing at $5.00 per million tokens, but Opus charges $25.00 per million output tokens versus GPT-5.5's $30.00. At 100M input/30M output monthly, that's $1,250 versus $1,400.

How do the context windows compare between Claude Opus 4.8 and GPT-5.5?

Claude Opus 4.8 offers a significantly larger context window at 1M tokens compared to GPT-5.5's 400K — more than double. For large codebases or lengthy documents, that's a meaningful practical difference beyond price.

Is the price difference between these two flagship models significant?

At standard volumes the gap is modest — about 12% on output pricing, roughly $150/month at 100M/30M tokens. Context window and task-specific performance will usually matter more than this cost gap.

Which model makes more sense for output-heavy workloads like content generation?

Since both charge the same for input but GPT-5.5 costs more per output token, Claude Opus 4.8 has a slight edge for output-heavy workloads like long-form content generation, where output volume dominates total cost.

HEAD-TO-HEAD · FLAGSHIP-TIER · VERIFIED 15 JUL 2026

Claude Opus 4.8 vs GPT-5.5: which is actually cheaper?

Both are flagship-tier models from different providers, which makes this one of the more genuinely useful head-to-head comparisons on this site — same rough capability class, real price and context differences worth knowing before you pick.

Spec	Claude Opus 4.8	GPT-5.5
Provider	Anthropic	OpenAI
Input / 1M tokens	$5.00	$5.00
Output / 1M tokens	$25.00	$30.00
Context window	1M	400K

The output price gap

Claude Opus 4.8 is 1.2x cheaper than GPT-5.5 on output tokens specifically — the number that matters most for any workload that generates more than it reads, like drafting or content generation. For input-heavy workloads the gap is different; check the table above directly for your specific ratio.

Context window

Claude Opus 4.8 offers the larger context window of the two at 1M tokens. If your task needs to hold a large document, codebase, or long conversation history in a single call, that ceiling can matter more than the per-token price difference.

Worked example

At 100M input and 30M output tokens a month — a realistic flagship-tier workload — Claude Opus 4.8 runs about $1,250.00/month and GPT-5.5 runs about $1,400.00/month on standard list pricing.

Prices verified against each provider's official documentation, 15 July 2026. Use the calculator with your own usage for an exact comparison, or see the full price table for every tracked model.