GPT-5.5 vs Grok 4
Compare pricing, context windows, and strengths for GPT-5.5 by OpenAI and Grok 4 by xAI - 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-5.5Grok 4
A flagship multimodal model excelling in natural language, math, and deep reasoning with unmatched all-around performance.
View Grok 4GPT-5.5 vs Grok 4 at a glance
Specs and pricing side by side, from the Appaca AI models directory.
| Spec | GPT-5.5 | Grok 4 |
|---|---|---|
| Provider | OpenAI | xAI |
| Model type | Text | Text |
| Context window | 1M tokens | 256K tokens |
| Input price | $5 / 1M tokens | $3 / 1M tokens |
| Output price | $30 / 1M tokens | $15 / 1M tokens |
| Status | Current | Current |
How GPT-5.5 and Grok 4 differ
What the numbers mean in practice when choosing between GPT-5.5 and Grok 4.
Our take
GPT-5.5 is the more capable generalist, with stronger coding benchmarks and a context window roughly four times larger. Grok 4 is cheaper on input ($3 vs $5 per million tokens) and is known for up-to-date knowledge, which suits fast-moving research and analysis tasks. For long-running agentic workflows GPT-5.5 is the safer default.
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Grok 4's 256K context is generous but well short of GPT-5.5's 1M tokens for whole-codebase or archive-scale work.
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Output pricing is close ($30 vs $15 per million tokens in GPT-5.5 vs Grok 4 respectively), so output-heavy tools run cheaper on Grok 4.
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Both are strong reasoning models; Grok 4's recency focus makes it popular for market and news analysis tools.
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Grok 4 is 40% cheaper on input tokens ($3 vs $5 per million), which adds up quickly in document-heavy workloads.
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Grok 4 is 50% cheaper on output tokens ($15 vs $30 per million) - the bigger factor for tools that generate long documents.
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GPT-5.5's 1M tokens context window is roughly 3.9x larger than Grok 4's 256K 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-5.5
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.
Grok 4
1. Flagship-level reasoning and math performance
- Designed for world-class reasoning depth, precision, and multi-step logical chains.
- Excels at STEM, mathematics, symbolic operations, proofs, and analytical workloads.
2. Powerful multimodal understanding
- Supports text, images, and other modalities.
- Handles cross-modal reasoning tasks requiring context synthesis.
3. Extreme capability across diverse tasks
- Positioned as a top-tier 'jack of all trades' model.
- Strong in natural language, coding, knowledge retrieval, and structured generation.
4. Large 256K context window
- Enables analysis of long documents, entire codebases, multi-document packs, and extensive agent sessions.
- Supports workloads that require persistent reasoning across large inputs.
5. Advanced developer tooling support
- Function calling for tool-augmented workflows.
- Structured outputs for predictable, schema-controlled generation.
- Integrates smoothly with agents and complex automation pipelines.
6. Efficient caching for cost reduction
- Cached input tokens discounted to $0.75 / 1M tokens.
- Encourages RAG, retrieval pipelines, and multi-step conversational workflows.
7. Production-ready performance
- Stable rate limits: 480 requests per minute.
- High token throughput: 2,000,000 tokens per minute.
- Available across multiple xAI regional clusters.
8. Optional Live Search augmentation
- Add-on: $25 per 1K sources.
- Enhances factual accuracy and real-time information retrieval.
Use GPT-5.5 or Grok 4 - or both
Appaca is the AI workspace for operators. Build internal tools and AI co-workers powered by GPT-5.5 or Grok 4 - 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 Grok 4. No code, no API keys, no deployment.
Switch models without rebuilding
Start on GPT-5.5, test the same tool on Grok 4, 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 Grok 4 - connected to the tools you already use.
Related comparisons
See how GPT-5.5 and Grok 4 stack up against other models in the directory.
FAQs
Grok 4 is generally cheaper: $3 input / $15 output per million tokens, versus $5 / $30 for GPT-5.5. Actual cost depends on how many tokens your workload reads and writes.
GPT-5.5 has the larger context window at 1M tokens, compared to 256K tokens for Grok 4. A larger window means the model can consider more text at once - useful for long contracts, codebases, or months of records.
GPT-5.5 is the more capable generalist, with stronger coding benchmarks and a context window roughly four times larger. Grok 4 is cheaper on input ($3 vs $5 per million tokens) and is known for up-to-date knowledge, which suits fast-moving research and analysis tasks. For long-running agentic workflows GPT-5.5 is the safer default.
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, Grok 4, 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 Grok 4
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.