Standard Compute
Cost per coding-agent request

Is Claude Opus 4.8 or GPT-5.3-Codex cheaper for coding agents?

For coding agents, Claude Opus 4.8 costs 2.7x as much as GPT-5.3-Codex per request ($0.15 vs $0.055 on our measured traffic), because Opus 4.8's input and cache rates are 2.9 times Codex's.

List prices: Anthropic pricing, OpenAI API pricing, checked 2026-10-13. Request costs: Standard Compute gateway data, 79,301 coding-agent requests from 75 users, Sep 13 to Oct 12, 2026. How we compute this

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Cost per coding-agent request, side by side

Cost at list priceGPT-5.3-CodexOpus 4.8
Prompt under 100K tokens50% of requests, 87% of input cached$0.030$0.079
Prompt of 100K to 272K39% of requests, 88% of input cached$0.073$0.20
Prompt over 272K tokens11% of requests, 86% of input cached$0.13$0.37
Average request$0.055$0.15
100 requests$5.55$14.91
Median session16 requests; a session ends after 10 idle minutes$0.74$1.93
A month of regular usemedian of 20 users active on 5+ days$84.36$231

Each logged request priced at the vendor's list rates for its own token counts, including cache reads and any higher rate for long prompts. Average output: 698 tokens per request. Both models are priced on the requests up to 400K tokens that fit in both context windows; band shares above describe all requests.

What to watch for

Codex's 400K window cannot take 3% of requests, so the comparison uses requests both can take. Both are older: Claude Opus 5.5 costs $0.11 per request and GPT-6.1 Sol $0.067.

FAQ

Is GPT-5.3-Codex cheaper than Claude Opus 4.8 for coding agents?
Yes, at list prices. 100 average coding-agent requests cost $5.55 on GPT-5.3-Codex and $14.91 on Claude Opus 4.8. A median 16-request session costs $0.74 vs $1.93. Measured on 79,301 real coding-agent requests (Sep 13 to Oct 12, 2026), counting only the requests up to 400K tokens that both can take.
How much does a month of Opus 4.8 vs GPT-5.3-Codex cost?
For the median regular user in our data (1,478 requests in 30 days), about $231 on Claude Opus 4.8 and $84.36 on GPT-5.3-Codex at list price. Heavier users pay proportionally more.
Claude Opus 4.8 vs GPT-5.3-Codex: which is better for agents?
Claude Opus 4.8 scores higher on output quality (9.4/10 vs 8.8/10), while GPT-5.3-Codex is the cheaper option. Claude Opus 4.8 is best for hard, high-stakes coding and reasoning where quality matters more than cost; GPT-5.3-Codex is best for codex CLI users and dedicated coding agents. Live community votes on this page show what people actually prefer.
Can I switch between Claude Opus 4.8 and GPT-5.3-Codex in the same agent?
Yes. Model-agnostic agents (Cline, Aider, OpenClaw, Hermes Agent, Kilo Code, OpenCode, Continue) let you swap models per task — many people route hard tasks to the stronger model and routine work to the cheaper one.

Community vote

Pick a winner in each dimension. You can change your vote any time.

Output Quality
Correctness and depth of what it produces
Agentic Ability
Tool calls, instruction-following, and multi-step tasks
Speed
Tokens per second and time-to-first-token
Value for money
How much capability you get per dollar
Reliability
Consistent results: fewer refusals, loops and format breaks

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