GPT-5 vs Claude Opus 4.8
Premium model showdown — GPT-5 is 64% cheaper, but Claude Opus 4.8 has 3.7x more context and top-tier reasoning.
Pricing data verified: Jun 6, 2026
| Specification | GPT-5 (OpenAI) | Claude Opus 4.8 (Anthropic) |
|---|---|---|
| Input Price (per 1M tokens) | $1.25 | $5.00 |
| Output Price (per 1M tokens) | $10.00 | $25.00 |
| Context Window | 272K tokens | 1M tokens |
| Tier | Premium | Premium |
| Provider | OpenAI | Anthropic |
| Cost at 1M input + 500K output | $6.25 | $17.50 |
Calculate Your Exact Costs
Enter your usage to see a precise cost comparison for both premium models.
Which Model for Which Use Case?
Complex Reasoning & Analysis
Claude Opus 4.8 excels at multi-step reasoning, nuanced analysis, and tasks requiring deep understanding. GPT-5 handles most reasoning well but at a fraction of the cost.
Long-Document Processing
Claude Opus 4.8's 1M context window can process entire codebases, legal documents, or research papers that GPT-5's 272K cannot fit. Essential for large-scale analysis.
Code Generation & Debugging
Both handle coding well. GPT-5 is dramatically cheaper for standard coding tasks. Opus 4.8's larger context helps when analyzing entire repositories or complex refactoring.
Chatbots & Customer Support
High-volume, shorter conversations where cost per request matters most. GPT-5's lower pricing makes it the clear winner for production chatbots at scale.
Need deeper cost analysis?
APIpulse Pro lets you compare all 34 models, save scenarios, and export PDF reports.
Frequently Asked Questions
Is GPT-5 cheaper than Claude Opus 4.8?
Yes, significantly. GPT-5 costs $1.25/M input and $10/M output. Claude Opus 4.8 costs $5/M input and $25/M output. GPT-5 is 75% cheaper on input and 60% cheaper on output. For a typical workload of 1M input + 500K output tokens/month, GPT-5 costs $6.25 vs Claude Opus 4.8's $17.50 — saving you $11.25/month (64%).
Which has a larger context window?
Claude Opus 4.8 has a 1M token context window, while GPT-5 has 272K. Claude Opus 4.8 offers 3.7x more context capacity, which is critical for processing very long documents, maintaining extended conversations, or handling large codebases in a single request.
When should I choose Claude Opus 4.8 over GPT-5?
Choose Claude Opus 4.8 when you need: (1) 1M+ token context for processing entire codebases or long documents, (2) complex multi-step reasoning where Opus's quality may justify the 4x price premium, (3) nuanced creative writing or analysis tasks. Choose GPT-5 when cost efficiency matters more and your inputs fit within 272K tokens.
Can I switch between GPT-5 and Claude Opus 4.8 easily?
Yes. Both use standard REST APIs. If you're using an abstraction layer like LangChain, LiteLLM, or Vercel AI SDK, switching is a one-line config change. The main differences are in API structure (OpenAI vs Anthropic format) and authentication methods (API key vs Anthropic key).