Compare Claude Opus 4.8 from Anthropic and GPT 5.3 Chat from OpenAI on key metrics including benchmarks, price, context length, and other model features. Access both models and hundreds of others through the AIHubMix API.
Claude Opus 4.8
GPT 5.3 ChatClaude Opus 4.8 is Anthropic’s newest and most powerful publicly available model. It is suitable for the most complex tasks. It is Anthropic’s strongest model for complex reasoning, long-horizon agent programming, and highly autonomous work.claude-opus-4-8 does not display thought content by default; you need to set the additional parameter "display": "summarized" to enable it
GPT-5.3Chat refers to the GPT-5.3 snapshot currently used in ChatGPT and is optimized for conversational use cases. While GPT-5.2 is recommended for most API applications, GPT-5.3Chat is ideal for testing the latest improvements in chat-based interactions.
Prices are per million tokens. Time to First Token and throughput are rolling averages measured on AIHubMix.
Promotional prices show the discounted rate; see each model page for promotion windows.
Daily traffic served through AIHubMix — how demand for each model is trending.
Measured on real AIHubMix traffic, hourly buckets. Gaps mean no traffic in that hour.
LMArena ratings by capability (Bradley-Terry, commonly called Elo). Higher is better.
Source: LMArena (arena.ai) leaderboard, imported by AIHubMix. Models without published ratings are omitted per chart.
Estimate your monthly bill for the same workload on each model.
Monthly = daily × 30. Discounted rates applied where a promotion is active.
GPT 5.3 Chat: $14/M output tokens; Claude Opus 4.8: $25/M. Use the cost calculator above to estimate your own workload.
Claude Opus 4.8: 1527; GPT 5.3 Chat: 1497 (LMArena coding leaderboard).
GPT 5.3 Chat: 0.8s time to first token measured on AIHubMix; see the live performance charts above for how each model behaves across the day.
Claude Opus 4.8 accepts 1,000,000 and GPT 5.3 Chat accepts 128,000 input tokens. Maximum output per request is 128,000 tokens on Claude Opus 4.8 and 16,384 tokens on GPT 5.3 Chat.
GPT 5.3 Chat at 99.7 tok/s and Claude Opus 4.8 at 82.6 tok/s, measured as output throughput on AIHubMix — a separate metric from time to first token.
Claude Opus 4.8 accepts text, image and PDF input and supports thinking, tool calling, function calling and structured outputs; GPT 5.3 Chat accepts text and image input and supports function calling and structured outputs.
Yes. AIHubMix serves every model on this page behind one OpenAI-compatible endpoint, so switching between them is a one-line change to the model field — no second account, key or SDK.
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