gpt-oss-20b vs GLM 5.1
At a Glance
| Compare |  gpt-oss-20bOpenAI |  GLM 5.1Z.ai |
|---|---|---|
| Pricing and Limits | ||
| Input priceFrom · USD / 1M tokens | $0.030Deepinfra ↗ · Sep 21, 2026 | $1.05Deepinfra ↗ · Sep 21, 2026 |
| Output priceFrom · USD / 1M tokens | $0.13Openrouter ↗ · Sep 22, 2026 | $3.50Deepinfra ↗ · Sep 21, 2026 |
| Context windowMaximum documented tokens | 131K | 203K |
| Model facts checked | Aug 28, 2026View model evidence → | Aug 28, 2026View model evidence → |
Token prices are the lowest available sourced USD rates; input and output may use different providers. Cost ranking estimates output spend on LiveBench, not a full request bill. Ranking methodology →
Available Benchmarks
| Benchmark | gpt-oss-20b | GLM-5.1 |
|---|---|---|
| LMArena Text Arenatext-2026-09-13-d25aabda0010 · arena_rating · leader | 1,287.3288% of row best · rating · gpt-oss-20b; 95% CI [1280.92242279, 1293.71473349]; votes 10393; rank 246 | 1,462.38100% of row best · rating · glm-5.1; 95% CI [1458.52340519, 1466.22702609]; votes 48901; rank 33 |
| Overall ResultCounted from the protocol-matched rows above | 0 benchmark winsNo overall winner | 1 benchmark winNo overall winner |
Third-party benchmark Only like-for-like primary-publisher results are shown; raw scores, relative scores, configuration, and token spend remain visible.
Side-by-Side Facts
| Field | gpt-oss-20b | GLM-5.1 |
|---|---|---|
| Developer | OpenAI | Z.ai |
| Family | Gpt Oss | Glm 5 1 |
| Model | gpt-oss-20b | GLM-5.1 |
| Version | gpt-oss-20b | GLM-5.1 |
| Lifecycle | active | active |
| Released | Unknown | Unknown |
| Knowledge cutoff | Unknown | Unknown |
| Input modalities | Text | Text |
| Output modalities | Text | Text |
| Context window | 131K | 203K |
| Total parameters | 20.9B | 753.9B |
| Active parameters | 3.6B | Unknown |
| License | apache-2.0 | mit |
| Open weights | Yes | Yes |
| API available | Yes | Yes |
| Self-hostable | Yes | Yes |
| Provider access | Deepinfra (Standard), Groq (Standard), Hugging Face (Standard), Openrouter (Standard), Together Ai (Serverless, Standard) | Deepinfra (Standard), Hugging Face (Standard), Openrouter (Standard), Together Ai (Standard) |
| Capabilities | chat, generation, reasoning, tools | chat, generation, reasoning, tools |
gpt-oss-20b Capabilities
GLM 5.1 Capabilities
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Primary Evidence
Sources and Freshness
Questions
gpt-oss-20b vs GLM 5.1 FAQs
Is gpt-oss-20b or GLM 5.1 better for coding?+
This comparison does not currently contain a protocol-matched coding benchmark for both gpt-oss-20b and GLM 5.1, so Model Markets cannot name a coding leader from pricing, context size, or capability labels alone.
Which is cheaper, gpt-oss-20b or GLM 5.1?+
gpt-oss-20b is $0.030 and GLM 5.1 is $1.05 per million tokens, so gpt-oss-20b is cheaper on this metric. gpt-oss-20b is $0.13 and GLM 5.1 is $3.50 per million tokens, so gpt-oss-20b is cheaper on this metric.
Which has a larger context window, gpt-oss-20b or GLM 5.1?+
GLM 5.1 has the larger sourced context window. gpt-oss-20b supports 131K and GLM 5.1 supports 203K.
Which performs better in benchmarks, gpt-oss-20b or GLM 5.1?+
There is no overall benchmark winner: At least two independently verified, protocol-matched benchmarks are required for an overall winner.
Can gpt-oss-20b or GLM 5.1 be self-hosted?+
Both models have the same recorded self-hosting status: supported. gpt-oss-20b is open weight; GLM 5.1 is open weight.
Can gpt-oss-20b and GLM 5.1 understand images?+
gpt-oss-20b is not documented with image input; GLM 5.1 is not documented with image input. This reflects supported input modalities, not vision quality.
Which can generate longer answers, gpt-oss-20b or GLM 5.1?+
Neither has a larger sourced maximum output. gpt-oss-20b is — and GLM 5.1 is —.
Do gpt-oss-20b and GLM 5.1 support reasoning and tool use?+
gpt-oss-20b: reasoning and tool calling. GLM 5.1: reasoning and tool calling. Feature support does not establish relative quality.
Which is available from more inference providers, gpt-oss-20b or GLM 5.1?+
gpt-oss-20b has 5 sourced provider routes; GLM 5.1 has 4, so gpt-oss-20b has broader tracked availability.
Which offers better value, gpt-oss-20b or GLM 5.1?+
There is no universal value winner. Compare the input and output prices above with the matched benchmark result for your workload: cheaper tokens can be offset by different quality, token usage, latency, or provider availability.