API cost decision in 10 seconds
GPT-5.3-Codex vs 🔥Claude Opus 4.6
Pick GPT-5.3-Codex for lower cost; pick Claude Opus 4.6 only if the larger context window matters more.
Budget verdict
Pick GPT-5.3-Codex for lower cost; pick Claude Opus 4.6 only if the larger context window matters more.
On the standard 1M input plus 500K output workload, GPT-5.3-Codex is estimated at $8.75 vs $17.5 for Claude Opus 4.6, saving $8.75 (50% lower).
Claude Opus 4.6 has more context, but GPT-5.3-Codex saves $8.75 on the standard workload. At 10x that traffic, the same price gap is about $87.5. Use the calculator below to replace the sample workload with your own token volume.
Cost sensitivity
Workload Sensitivity
GPT-5.3-Codex stays cheaper across input-heavy, balanced, and output-heavy sample workloads.
| Workload shape | Token mix | Better pick | GPT-5.3-Codex | Claude Opus 4.6 |
|---|---|---|---|---|
| Input-heavy / RAG | 5M input + 500K output | GPT-5.3-Codex | $15.75 | $37.5 |
| Balanced workload | 1M input + 1M output | GPT-5.3-Codex | $15.75 | $30 |
| Output-heavy chatbot | 1M input + 5M output | GPT-5.3-Codex | $71.75 | $130 |
Estimate your workload cost
Your Workload Cost
This estimate uses normalized public API pricing per 1M tokens. It is a planning aid, not a billing quote. Verify provider pricing, limits, and terms before production use.
Quick Decision
GPT-5.3-Codex has the lower input price, GPT-5.3-Codex has the lower output price, and Claude Opus 4.6 offers the larger context window.
For a 1M input token plus 500K output token workload, the estimated API cost is $8.75 for GPT-5.3-Codex and $17.5 for Claude Opus 4.6.
Choose GPT-5.3-Codex when you care most about lower input-token price, and lower output-token price.
Choose Claude Opus 4.6 when you care most about larger context window.
| Feature | GPT-5.3-Codex (OpenAI) | 🔥Claude Opus 4.6 (Anthropic) |
|---|---|---|
| Input Price prompt tokens per 1M | $1.75 | $5 |
| Completion Price per 1M tokens | $14 | $25 |
| Sample Workload Cost 1M input + 500K output | $8.75 | $17.5 |
| Context Window | 400K | 1M |
| Release Date | 2026-02-24 | 2026-02-04 |
| Popularity | #18 |
GPT-5.3-Codex is OpenAI’s most advanced agentic coding model, combining the frontier software engineering performance of GPT-5.2-Codex with the broader reasoning and professional knowledge capabilities of GPT-5.2. It achieves state-of-the-art results...
Opus 4.6 is Anthropic’s strongest model for coding and long-running professional tasks. It is built for agents that operate across entire workflows rather than single prompts, making it especially effective...
Use-Case Decision Matrix
| Use case | Better pick | Why |
|---|---|---|
| Budget-constrained production | GPT-5.3-Codex | On the standard 1M input plus 500K output workload, GPT-5.3-Codex is estimated at $8.75 vs $17.5 for Claude Opus 4.6, saving $8.75 (50% lower). |
| High-volume input processing | GPT-5.3-Codex | Lower prompt-token price matters most when prompts or retrieved passages dominate the bill. |
| Long responses and chatbots | GPT-5.3-Codex | Lower output-token price matters most when assistants generate many completion tokens. |
| RAG or long-document work | Claude Opus 4.6 | A larger context window leaves more room for retrieved passages and source files. |