GPT-5.5 vs Claude 4.8 Opus
Compare pricing, context windows, and strengths for GPT-5.5 by OpenAI and Claude 4.8 Opus by Anthropic - and see how to put either to work in Appaca.
GPT-5.5
OpenAI's smartest and most capable model yet for agentic coding, knowledge work, and computer use, delivering a new class of intelligence at GPT-5.4 latency.
View GPT-5.5Claude 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-5.5 vs Claude 4.8 Opus at a glance
Specs and pricing side by side, from the Appaca AI models directory.
| Spec | GPT-5.5 | Claude 4.8 Opus |
|---|---|---|
| Provider | OpenAI | Anthropic |
| Model type | Text | Text |
| Context window | 1M tokens | 1M tokens |
| Input price | $5 / 1M tokens | $5 / 1M tokens |
| Output price | $30 / 1M tokens | $25 / 1M tokens |
| Status | Current | Current |
How GPT-5.5 and Claude 4.8 Opus differ
What the numbers mean in practice when choosing between GPT-5.5 and Claude 4.8 Opus.
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Both models cost the same on input: $5 per million tokens.
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Claude 4.8 Opus is 17% cheaper on output tokens ($25 vs $30 per million) - the bigger factor for tools that generate long documents.
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Both models offer the same 1M tokens context window.
Strengths side by side
Where each model shines, according to benchmarks and provider positioning.
GPT-5.5
1. Strongest Agentic Coding Model
- State-of-the-art on Terminal-Bench 2.0 (82.7%), Expert-SWE (73.1%), and SWE-Bench Pro (58.6%), outperforming GPT-5.4 on complex coding tasks.
- Holds context across large systems, reasons through ambiguous failures, and carries changes through surrounding codebases with fewer tokens.
2. Higher Intelligence at GPT-5.4 Latency
- Co-designed, trained, and served on NVIDIA GB200/GB300 NVL72 systems to match GPT-5.4 per-token latency while performing at a significantly higher level.
- Uses fewer tokens to complete the same tasks, making it more efficient as well as more capable.
3. Powerful for Knowledge Work & Computer Use
- Scores 84.9% on GDPval (44 occupations) and 78.7% on OSWorld-Verified for autonomous computer operation.
- Excels at generating documents, spreadsheets, and reports; naturally moves across finding information, using tools, and checking output.
4. Scientific Research Co-Scientist
- Leading performance on GeneBench, BixBench, and FrontierMath; helped discover a new proof about Ramsey numbers verified in Lean.
- Strong enough to meaningfully accelerate progress at the frontiers of biomedical and mathematical research.
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-5.5 or Claude 4.8 Opus - or both
Appaca is the AI workspace for operators. Build internal tools and AI co-workers powered by GPT-5.5 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-5.5 or Claude 4.8 Opus. No code, no API keys, no deployment.
Switch models without rebuilding
Start on GPT-5.5, 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-5.5 or Claude 4.8 Opus - connected to the tools you already use.
Related comparisons
See how GPT-5.5 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 $5 / $30 for GPT-5.5. Actual cost depends on how many tokens your workload reads and writes.
They are equal: both GPT-5.5 and Claude 4.8 Opus support a 1M tokens context window.
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-5.5, 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-5.5, 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-5.5 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.