GPT-5 Pro vs Claude 4.8 Opus
Compare pricing, context windows, and strengths for GPT-5 Pro by OpenAI and Claude 4.8 Opus by Anthropic - and see how to put either to work in Appaca.
GPT-5 Pro
A premium GPT-5 variant that uses more compute to deliver consistently smarter, more precise reasoning for the toughest problems.
View GPT-5 ProClaude 4.8 Opus
Anthropic's flagship model for coding and agents, building on Opus 4.7 with stronger reliability, a cheaper fast mode, and gains across coding, computer use, and professional work.
View Claude 4.8 OpusGPT-5 Pro vs Claude 4.8 Opus at a glance
Specs and pricing side by side, from the Appaca AI models directory.
| Spec | GPT-5 Pro | Claude 4.8 Opus |
|---|---|---|
| Provider | OpenAI | Anthropic |
| Model type | Text | Text |
| Context window | 400K tokens | 1M tokens |
| Input price | $15 / 1M tokens | $5 / 1M tokens |
| Output price | $120 / 1M tokens | $25 / 1M tokens |
| Status | Current | Current |
How GPT-5 Pro and Claude 4.8 Opus differ
What the numbers mean in practice when choosing between GPT-5 Pro and Claude 4.8 Opus.
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Claude 4.8 Opus is 67% cheaper on input tokens ($5 vs $15 per million), which adds up quickly in document-heavy workloads.
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Claude 4.8 Opus is 79% cheaper on output tokens ($25 vs $120 per million) - the bigger factor for tools that generate long documents.
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Claude 4.8 Opus's 1M tokens context window is roughly 2.5x larger than GPT-5 Pro's 400K tokens, so it can work across bigger codebases, contracts, or archives in one pass.
Strengths side by side
Where each model shines, according to benchmarks and provider positioning.
GPT-5 Pro
1. Highest reasoning quality in the GPT-5 family
- Uses significantly more compute to "think harder" before responding.
- Designed for the toughest reasoning tasks where answer quality matters more than speed.
- Produces more precise, reliable, and detailed outputs than standard GPT-5.
2. Advanced multi-turn reasoning via Responses API
- Available only in the Responses API to support:
- Multi-turn internal model interactions before returning a reply.
- Advanced control patterns (e.g., background mode for long-running jobs).
- Ideal for complex workflows, deep planning, and multi-step analysis.
3. Configured for maximum effort by default
- Always runs with reasoning.effort: 'high' (no lower-effort mode).
- Prioritizes depth and correctness over latency and cost.
4. Multimodal input
- Accepts text + image as input.
- Outputs text, with strong instruction-following and analysis capabilities.
5. Tooling and ecosystem integration
- Supports Web Search, File Search, and Image Generation (as tools).
- Supports MCP and other Responses API tooling patterns.
- Does not support Code Interpreter and does not support Computer Use, keeping focus on pure reasoning + tools.
Claude 4.8 Opus
1. Modest but tangible gains across the board
- 69.2% on SWE-bench Pro (+4.9 points over Opus 4.7's 64.3%), 88.6% on SWE-bench Verified, and a 1,890 Elo on GDPval-AA - about 121 Elo ahead of GPT-5.5.
- Anthropic frames it as an incremental refinement of Opus 4.7 rather than a step-change release.
2. The most reliable agent model Anthropic has shipped
- The only model to complete every case end-to-end on Anthropic's internal Super-Agent benchmark, beating prior Opus models and GPT-5.5 at parity on cost.
- Leads CursorBench across every effort level with more efficient tool calling - fewer steps for the same intelligence.
- 84% on Online-Mind2Web and stronger OSWorld-Verified scores make it the strongest computer-use and browser-agent model Anthropic has tested.
3. New highs for professional and legal work
- Highest score ever recorded on Anthropic's Legal Agent Benchmark, and the first model to break 10% on its all-pass standard.
- Roughly a 4x improvement in honesty and calibrated uncertainty versus Opus 4.7 on Anthropic's evaluations.
4. Cheaper, faster controls
- Standard pricing holds at $5/M input and $25/M output, unchanged from Opus 4.7.
- Fast mode now runs at 2.5x speed for $10/M input and $50/M output - about a third of what fast mode cost on prior Opus releases.
- A new effort dial gives finer control over how hard the model works before answering.
5. Long-horizon agent workflows
- 1M token context window in beta and up to 128K output tokens.
- Introduces Dynamic Workflows (research preview) in Claude Code - Opus can write its own orchestration script and run up to 16 concurrent / 1,000 total subagents in a single session.
Use GPT-5 Pro or Claude 4.8 Opus - or both
Appaca is the AI workspace for operators. Build internal tools and AI co-workers powered by GPT-5 Pro or Claude 4.8 Opus - connected to your real data and ready for your whole team. No code, no deployment.
Describe it, and it's built
Tell the Appaca agent the internal tool you need and it builds a working app powered by GPT-5 Pro or Claude 4.8 Opus. No code, no API keys, no deployment.
Switch models without rebuilding
Start on GPT-5 Pro, test the same tool on Claude 4.8 Opus, and keep whichever performs better - the rest of your app stays exactly as it is.
Automated for the whole team
Schedule tools to run on autopilot - daily digests, weekly reports, real-time triggers - and share them with your whole team from one workspace.
Describe it, and it's built
Tell the Appaca agent what your team needs and it builds a working app powered by GPT-5 Pro or Claude 4.8 Opus - connected to the tools you already use.
Related comparisons
See how GPT-5 Pro and Claude 4.8 Opus stack up against other models in the directory.
FAQs
Claude 4.8 Opus is generally cheaper: $5 input / $25 output per million tokens, versus $15 / $120 for GPT-5 Pro. Actual cost depends on how many tokens your workload reads and writes.
Claude 4.8 Opus has the larger context window at 1M tokens, compared to 400K tokens for GPT-5 Pro. A larger window means the model can consider more text at once - useful for long contracts, codebases, or months of records.
It depends on the job. Compare the pricing, context window, and strengths above against your workload - and remember the choice isn't permanent. In Appaca you can build a tool on GPT-5 Pro, test the same tool on Claude 4.8 Opus, and switch at any time without rebuilding anything.
Yes. Appaca is a no-code AI workspace: describe the internal tool your team needs and the Appaca agent builds it as a working app powered by GPT-5 Pro, Claude 4.8 Opus, or any other model in the directory - with a built-in database, team access, and integrations. No API keys to wire up and nothing to deploy.
Build AI tools with GPT-5 Pro or Claude 4.8 Opus
Describe the tool your team needs and get a working app powered by the model you choose - with a built-in database, team access, and integrations. No code, no deployment.