GLM-5.1 vs GPT-4.1 Mini
GLM-5.1 (2026) and GPT-4.1 Mini (2025) are frontier reasoning models from Zhipu AI and OpenAI. GLM-5.1 ships a 200k-token context window, while GPT-4.1 Mini ships a 1.05m-token context window. On pricing, GPT-4.1 Mini costs $0.40/1M input tokens versus $0.98/1M for the alternative. This comparison covers specs, pricing, API access, capabilities, benchmarks, input and output token costs, and production fit for coding and agent workloads.
GPT-4.1 Mini is ~145% cheaper at $0.40/1M; pay for GLM-5.1 only for coding workflow support.
Decision scorecard
Local evidence first| Signal | GLM-5.1 | GPT-4.1 Mini |
|---|---|---|
| Best for | reasoning-heavy apps, tool-calling agents, and provider-routed production | multimodal apps, tool-calling agents, and long-context analysis |
| Decision fit | Coding, RAG, and Agents | Coding, RAG, and Agents |
| Context window | 200k | 1.05m |
| Cheapest output | $3.08/1M tokens | $1.60/1M tokens |
| Provider routes | 5 tracked | 4 tracked |
| Shared benchmarks | 0 rows | 0 rows |
Decision tradeoffs
- GLM-5.1 has broader tracked provider coverage for fallback and procurement flexibility.
- GLM-5.1 uniquely exposes Reasoning in local model data.
- Local decision data tags GLM-5.1 for Coding, RAG, and Agents.
- GPT-4.1 Mini has the larger context window for long prompts, retrieval packs, or transcript analysis.
- GPT-4.1 Mini has the lower cheapest tracked output price at $1.60/1M tokens.
- GPT-4.1 Mini uniquely exposes Vision and Multimodal in local model data.
- Local decision data tags GPT-4.1 Mini for Coding, RAG, and Agents.
Monthly cost at traffic
Estimate token spend from the cheapest tracked input and output route or tier on this page.
GLM-5.1
$1,554
Cheapest tracked route/tier: Z.ai
GPT-4.1 Mini
$720
Cheapest tracked route/tier: OpenRouter
Estimated monthly gap: $834. Batch, cache, alternate speed tiers, and negotiated pricing are excluded from this local estimate.
Switch friction
- Provider overlap exists on OpenRouter and Vercel AI Gateway; start route-level A/B tests there.
- GPT-4.1 Mini is $1.48/1M tokens lower on cheapest tracked output pricing before cache, batch, or negotiated discounts.
- Check replacement coverage for Reasoning before moving production traffic.
- GPT-4.1 Mini adds Vision and Multimodal in local capability data.
- Provider overlap exists on OpenRouter and Vercel AI Gateway; start route-level A/B tests there.
- GLM-5.1 is $1.48/1M tokens higher on cheapest tracked output pricing, so quality gains need to justify the spend.
- Check replacement coverage for Vision and Multimodal before moving production traffic.
- GLM-5.1 adds Reasoning in local capability data.
Specs
| Specification | ||
|---|---|---|
| Released | 2026-04-07 | 2025-04-01 |
| Context window | 200k | 1.05m |
| Parameters | 754B total, 40B active | — |
| Architecture | mixture of experts | decoder only |
| License | MIT | Proprietary |
| Knowledge cutoff | 2025-11 | 2025-01 |
Pricing and availability
| Pricing attribute | GLM-5.1 | GPT-4.1 Mini |
|---|---|---|
| Input price | $0.98/1M tokens | $0.40/1M tokens |
| Output price | $3.08/1M tokens | $1.60/1M tokens |
| Providers |
Capabilities
| Capability | GLM-5.1 | GPT-4.1 Mini |
|---|---|---|
| Vision | No | Yes |
| Multimodal | No | Yes |
| Reasoning | Yes | No |
| Function calling | Yes | Yes |
| Tool use | Yes | Yes |
| Structured outputs | Yes | Yes |
| Code execution | Yes | Yes |
| IDE integration | No | No |
| Computer use | No | No |
| Parallel agents | No | No |
Benchmarks
No shared benchmark rows are currently sourced for this pair.
Deep dive
The capability footprint differs most on vision: GPT-4.1 Mini, multimodal input: GPT-4.1 Mini, and reasoning mode: GLM-5.1. Both models share function calling, tool use, structured outputs, and code execution, so the practical split is not just feature count. Use those differences to decide whether the page is about raw model quality, agentic coding support, multimodal ingestion, or predictable structured API behavior.
For cost, GLM-5.1 lists $0.98/1M input and $3.08/1M output tokens on the cheapest tracked provider, while GPT-4.1 Mini lists $0.40/1M input and $1.60/1M output tokens on the cheapest tracked provider. A 70/30 input-output blend puts GPT-4.1 Mini lower by about $0.85 per million blended tokens. Availability is 5 providers versus 4, so concentration risk also matters.
Choose GLM-5.1 when coding workflow support and broader provider choice are central to the workload. Choose GPT-4.1 Mini when coding workflow support, larger context windows, and lower input-token cost are more important. For production, rerun your own prompts through the exact provider, region, and tool stack you plan to ship. This keeps the decision grounded in measurable tradeoffs instead of brand-level assumptions. It also helps separate model capability from provider packaging, which can change cost and latency.
FAQ
Which has a larger context window, GLM-5.1 or GPT-4.1 Mini?
GPT-4.1 Mini supports 1.05m tokens, while GLM-5.1 supports 200k tokens. That gap matters most for long documents, large codebases, retrieval-heavy agents, and conversations where earlier context must remain visible. Use this as a quick comparison signal, then confirm the provider-specific limits before committing to production.
Which is cheaper, GLM-5.1 or GPT-4.1 Mini?
GPT-4.1 Mini is cheaper on tracked token pricing. GLM-5.1 costs $0.98/1M input and $3.08/1M output tokens. GPT-4.1 Mini costs $0.40/1M input and $1.60/1M output tokens. Provider discounts or batch pricing can still change the final bill.
Is GLM-5.1 or GPT-4.1 Mini open source?
GLM-5.1 is listed under MIT. GPT-4.1 Mini is listed under Proprietary. License labels affect whether you can self-host, redistribute weights, or rely only on hosted APIs, so confirm the upstream license before deployment.
Which is better for vision, GLM-5.1 or GPT-4.1 Mini?
GPT-4.1 Mini has the clearer documented vision signal in this comparison. If vision is mission-critical, validate it against the provider endpoint because model-level support and API-level exposure can differ. Use this as a quick comparison signal, then confirm the provider-specific limits before committing to production.
Which is better for multimodal input, GLM-5.1 or GPT-4.1 Mini?
GPT-4.1 Mini has the clearer documented multimodal input signal in this comparison. If multimodal input is mission-critical, validate it against the provider endpoint because model-level support and API-level exposure can differ.
Where can I run GLM-5.1 and GPT-4.1 Mini?
GLM-5.1 is available on Z.ai, OpenRouter, Fireworks AI, Vercel AI Gateway, and Novita AI. GPT-4.1 Mini is available on OpenRouter, Replicate API, OpenAI API, and Vercel AI Gateway. Provider coverage can affect latency, region availability, compliance posture, and fallback options.
Continue comparing
Last reviewed: 2026-05-25. Data sourced from public model cards and provider documentation.