Claude Opus 4.8 vs GPT-5 Pro: API Cost Comparison
Compare the API pricing, context windows, features, and real-world cost projections for Claude Opus 4.8 (Anthropic) and GPT-5 Pro (OpenAI). Use the interactive calculator below to compute your exact monthly cost based on your token usage and request volume.
Prices verified Jun 26, 2026
Interactive Cost Calculator
Fills in typical token counts for a workload type
Tokens in each prompt sent to the model
Tokens generated in each response
Total API calls per month
Showing costs for 2 models. Cheapest: Claude Opus 4.8 at $175.00/month.
| Alert | |||||||
|---|---|---|---|---|---|---|---|
BestClaude Opus 4.8 | Anthropic | $175.00 | $0.017500 | $50.00 | $125.00 | 76.7% | Alerts coming soon |
GPT-5 Pro | OpenAI | $750.00 | $0.075000 | $150.00 | $600.00 | — | Alerts coming soon |
Monthly Cost Comparison
Price Comparison at a Glance
All prices are in USD per 1 million tokens ($/M tokens). Lower is cheaper.
| Pricing Type | Claude Opus 4.8 | GPT-5 Pro | Cheaper |
|---|---|---|---|
| Input (standard) | $5.00/M | $15.00/M | Claude Opus 4.8 |
| Output | $25.00/M | $120.00/M | Claude Opus 4.8 |
| Batch input | N/A | $7.50/M | — |
| Batch output | N/A | $60.00/M | — |
Prices last verified: 2026-03-06 – 2026-06-26
Cost Breakdown by Usage Volume
Estimated monthly costs at different request volumes, assuming 1,000 input tokens and 500 output tokens per request. Adjust in the calculator above for your specific use case.
| Volume | Claude Opus 4.8Monthly | GPT-5 ProMonthly | Claude Opus 4.8Per request | GPT-5 ProPer request |
|---|---|---|---|---|
| 1K requests/mo | $17.50 | $75.00 | $0.017500 | $0.075000 |
| 10K requests/mo | $175.00 | $750.00 | $0.017500 | $0.075000 |
| 100K requests/mo | $1,750.00 | $7,500.00 | $0.017500 | $0.075000 |
| 1M requests/mo | $17,500.00 | $75,000.00 | $0.017500 | $0.075000 |
Green values indicate the lower-cost option at each volume tier. Cost per request is calculated at 1,000 input + 500 output tokens using standard (non-batch, non-cached) pricing.
Price History
Input price per 1M tokensWhen to Choose Claude Opus 4.8
by Anthropic
- General chatbot
Input / 1M tokens
$5.00/M
Output / 1M tokens
$25.00/M
Context window
1,000,000
Tier
premium
When to Choose GPT-5 Pro
by OpenAI
- Code generation
- Document summarization
Input / 1M tokens
$15.00/M
Output / 1M tokens
$120.00/M
Context window
400,000
Tier
premium
Key Differences Beyond Price
Cost is only one factor in choosing an AI model. Context window size, rate limits, supported features, and latency all affect whether a model fits your use case.
| Capability | Claude Opus 4.8 | GPT-5 Pro |
|---|---|---|
| Context window | 1,000,000 tokens | 400,000 tokens |
| Max output tokens | 128,000 tokens | 272,000 tokens |
| Performance tier | Premium | Premium |
| Vision / image input | Yes | Yes |
| Function calling | Yes | Yes |
| JSON mode | Yes | Yes |
| Prompt caching | No | No |
| Batch API (50% discount) | No | Yes |
| Extended reasoning | Yes | No |
| Fine-tuning | No | No |
| Rate limit (req/min) | Not published | 10,000 |
GPT-5 Pro notes
Enterprise Pro tier with batch API support.
Frequently Asked Questions
Is Claude Opus 4.8 cheaper than GPT-5 Pro?
At standard usage (1,000 input tokens, 500 output tokens, 100,000 requests/month), Claude Opus 4.8 costs $1,750.00/month versus $7,500.00/month for GPT-5 Pro — a 77% saving. Your actual savings will vary based on your token profile; output-heavy workloads amplify differences in output pricing.
Which model has a larger context window, Claude Opus 4.8 or GPT-5 Pro?
Claude Opus 4.8 has a larger context window at 1,000,000 tokens, compared to 400,000 tokens for GPT-5 Pro. A larger context window is important for processing long documents, multi-turn conversations, or large codebases without truncation.
Do Claude Opus 4.8 and GPT-5 Pro support the Batch API?
GPT-5 Pro supports the Batch API (50% discount for async processing), while Claude Opus 4.8 does not. If your workload tolerates up to 24-hour latency, routing to GPT-5 Pro with batch pricing could significantly cut costs versus Claude Opus 4.8's standard rate.
Which model offers better prompt caching?
Neither Claude Opus 4.8 nor GPT-5 Pro currently supports prompt caching. For prompt-caching capable alternatives, consider Claude models from Anthropic or GPT-4o from OpenAI.
What are the best use cases for Claude Opus 4.8 vs GPT-5 Pro?
Claude Opus 4.8 is best suited for General chatbot, while GPT-5 Pro is optimized for Code generation, Document summarization. Choose based on which use case matches your primary workload — and validate with the cost calculator above to confirm the total monthly spend fits your budget.
What is the cost per request for Claude Opus 4.8 vs GPT-5 Pro?
At 1,000 input tokens and 500 output tokens per request — a typical conversational workload — Claude Opus 4.8 costs $0.017500 per request and GPT-5 Pro costs $0.075000 per request. At 100,000 requests/month, that translates to $1,750.00 and $7,500.00 respectively. Use the interactive calculator to adjust these parameters for your actual workload.
Claude Opus 4.8 vs GPT-5 Pro: Summary
When comparing Claude Opus 4.8 and GPT-5 Pro for API cost, the right choice depends on your workload's token profile, required features, and tolerance for latency. Claude Opus 4.8 offers lower total cost at standard usage volumes (1,000 input + 500 output tokens per request at 100,000 requests/month) at $1,750.00/month, compared to $7,500.00/month for GPT-5 Pro.
Both models are priced in USD per million tokens, the standard unit across all major AI API providers. Claude Opus 4.8 charges $5.00/M for input tokens and $25.00/M for output tokens. GPT-5 Pro charges $15.00/M input and $120.00/M output. If your workload is output-heavy (more tokens generated than consumed as input), the model with the lower output price compounds cost savings significantly at scale.
Context window capacity differs between the two: Claude Opus 4.8 supports up to 1,000,000 tokens in a single request, versus 400,000 tokens for GPT-5 Pro. A larger context window is essential for document summarization, large codebase analysis, and multi-document retrieval-augmented generation (RAG) applications.
Use the interactive calculator at the top of this page to enter your actual token usage and monthly request volume for a precise cost comparison tailored to your workload. Adjust for batch API discounts and prompt caching to find the most cost-effective option for your specific deployment.
Related Comparisons
Explore other model comparisons from the same providers or performance tiers.
Related Provider Pages
View complete pricing tables and model lineups for the providers behind these models.
Relevant Use Cases
See cost recommendations for workloads where Claude Opus 4.8 or GPT-5 Pro is recommended.