GPT-5.6 Sol vs Claude Opus 4.8: API Cost Comparison (2026)
GPT-5.6 Sol or Claude Opus 4.8? Instead of comparing list prices, we compute the same workload on both (prices verified 2026-09-17). Spoiler: GPT-5.6 Sol wins on raw cost in most scenarios — but "when to pick each" matters more than the winner. Compare them live in the calculator.
| Rate per 1M tokens | GPT-5.6 Sol | Claude Opus 4.8 |
|---|---|---|
| Input | $4.00 | $5.00 |
| Cached input | $0.40 | $0.50 |
| Output | $20.00 | $25.00 |
Same workload, both models
| Monthly scenario | GPT-5.6 Sol | Claude Opus 4.8 | Difference |
|---|---|---|---|
| Support chatbot (150k requests, 400 in / 300 out tokens) | $1,140.00 | $1,425.00 | 20% in favor of GPT-5.6 Sol |
| Document workflow (22k runs, 3,000 in / 400 out tokens) | $440.00 | $550.00 | 20% in favor of GPT-5.6 Sol |
| High-volume classifier (1M requests, 300 in / 10 out tokens) | $1,400.00 | $1,750.00 | 20% in favor of GPT-5.6 Sol |
Your token shape decides: input-heavy workloads (documents, RAG) amplify the input-rate gap; output-heavy ones (content generation) weigh the output rate. Run your exact mix in the calculator with both preselected.
When to pick each
- GPT-5.6 Sol — when per-token cost rules: high volume, verifiable tasks, tight budgets. It comes out 20–20% cheaper in these scenarios.
- Claude Opus 4.8 — when the premium buys something you need (quality on your specific task, context, ecosystem). The only honest way to know: test your real case on both with a small sample.
- Both — the winning production pattern is often routing: easy requests to the cheap one, hard ones to the strong one.
Related guides: how AI API pricing works and how to reduce LLM costs.
Our read: at today's standard rates Sol is 20% cheaper than Opus 4.8 for both uncached input and output. Sol's rate is promotional, though, so annual forecasts should include a post-promotion scenario instead of assuming that gap is permanent.
Both models are expensive enough that quality failures dominate small token differences. Pilot them on your hardest real cases, record success and review time, and choose from total cost per accepted result.
Prices verified on 2026-09-17 against the provider's official pricing page. Estimates are for planning purposes only — always confirm current pricing with the provider.