GLM-5 Turbo vs gpt-oss-120b
GLM-5 Turbo (2026) and gpt-oss-120b (2025) are frontier reasoning models from Zhipu AI and OpenAI. GLM-5 Turbo ships a 200k-token context window, while gpt-oss-120b ships a 131k-token context window. On pricing, gpt-oss-120b costs $0.04/1M input tokens versus $1.20/1M 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-oss-120b is ~2977% cheaper at $0.04/1M; pay for GLM-5 Turbo only for reasoning depth.
Decision scorecard
Local evidence first| Signal | GLM-5 Turbo | gpt-oss-120b |
|---|---|---|
| Best for | reasoning-heavy apps, tool-calling agents, and provider-routed production | tool-calling agents and provider-routed production |
| Decision fit | RAG, Agents, and Long context | RAG, Agents, and Long context |
| Context window | 200k | 131k |
| Cheapest output | $4/1M tokens | $0.18/1M tokens |
| Provider routes | 2 tracked | 10 tracked |
| Shared benchmarks | 0 rows | 0 rows |
Decision tradeoffs
- GLM-5 Turbo has the larger context window for long prompts, retrieval packs, or transcript analysis.
- GLM-5 Turbo uniquely exposes Reasoning in local model data.
- Local decision data tags GLM-5 Turbo for RAG, Agents, and Long context.
- gpt-oss-120b has the lower cheapest tracked output price at $0.18/1M tokens.
- gpt-oss-120b has broader tracked provider coverage for fallback and procurement flexibility.
- Local decision data tags gpt-oss-120b for RAG, Agents, and Long context.
Monthly cost at traffic
Estimate token spend from the cheapest tracked input and output route or tier on this page.
GLM-5 Turbo
$1,960
Cheapest tracked route/tier: OpenRouter
gpt-oss-120b
$76.20
Cheapest tracked route/tier: OpenRouter
Estimated monthly gap: $1,884. 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-oss-120b is $3.82/1M tokens lower on cheapest tracked output pricing before cache, batch, or negotiated discounts.
- Check replacement coverage for Reasoning before moving production traffic.
- Provider overlap exists on OpenRouter and Vercel AI Gateway; start route-level A/B tests there.
- GLM-5 Turbo is $3.82/1M tokens higher on cheapest tracked output pricing, so quality gains need to justify the spend.
- GLM-5 Turbo adds Reasoning in local capability data.
Specs
| Specification | ||
|---|---|---|
| Released | 2026-03-01 | 2025-08-05 |
| Context window | 200k | 131k |
| Parameters | 744B total, 40B active | 120B |
| Architecture | mixture of experts | decoder only |
| License | Proprietary | Open Weights |
| Knowledge cutoff | 2025-11 | 2025-08 |
Pricing and availability
| Pricing attribute | GLM-5 Turbo | gpt-oss-120b |
|---|---|---|
| Input price | $1.20/1M tokens | $0.04/1M tokens |
| Output price | $4/1M tokens | $0.18/1M tokens |
| Providers |
Capabilities
| Capability | GLM-5 Turbo | gpt-oss-120b |
|---|---|---|
| Vision | No | No |
| Multimodal | No | No |
| Reasoning | Yes | No |
| Function calling | Yes | Yes |
| Tool use | Yes | Yes |
| Structured outputs | Yes | Yes |
| Code execution | No | No |
| 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 reasoning mode: GLM-5 Turbo. Both models share function calling, tool use, and structured outputs, 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 Turbo lists $1.20/1M input and $4/1M output tokens on the cheapest tracked provider, while gpt-oss-120b lists $0.04/1M input and $0.18/1M output tokens on the cheapest tracked provider. A 70/30 input-output blend puts gpt-oss-120b lower by about $1.96 per million blended tokens. Availability is 2 providers versus 10, so concentration risk also matters.
Choose GLM-5 Turbo when reasoning depth and larger context windows are central to the workload. Choose gpt-oss-120b when provider fit, lower input-token cost, and broader provider choice 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 Turbo or gpt-oss-120b?
GLM-5 Turbo supports 200k tokens, while gpt-oss-120b supports 131k 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 Turbo or gpt-oss-120b?
gpt-oss-120b is cheaper on tracked token pricing. GLM-5 Turbo costs $1.20/1M input and $4/1M output tokens. gpt-oss-120b costs $0.04/1M input and $0.18/1M output tokens. Provider discounts or batch pricing can still change the final bill.
Is GLM-5 Turbo or gpt-oss-120b open source?
GLM-5 Turbo is listed under Proprietary. gpt-oss-120b is listed under Open Weights. 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 reasoning mode, GLM-5 Turbo or gpt-oss-120b?
GLM-5 Turbo has the clearer documented reasoning mode signal in this comparison. If reasoning mode is mission-critical, validate it against the provider endpoint because model-level support and API-level exposure can differ.
Which is better for function calling, GLM-5 Turbo or gpt-oss-120b?
Both GLM-5 Turbo and gpt-oss-120b expose function calling. The better choice depends on benchmark fit, context budget, pricing, and whether your provider route exposes the same capability surface. Use this as a quick comparison signal, then confirm the provider-specific limits before committing to production.
Where can I run GLM-5 Turbo and gpt-oss-120b?
GLM-5 Turbo is available on OpenRouter and Vercel AI Gateway. gpt-oss-120b is available on Cloudflare Workers AI, OpenRouter, Together AI, Fireworks AI, and GCP Vertex AI. Provider coverage can affect latency, region availability, compliance posture, and fallback options.
Continue comparing
Last reviewed: 2026-05-22. Data sourced from public model cards and provider documentation.