GLM 5.1 is Z.ai's foundation model with a 200K-token context window for extended document processing and multi-turn reasoning.
- Strengths
- Handles long-form text and complex multi-step tasks within a wide context window, bridging the gap between earlier 4.x models and the newer 5.2+ generation.
- Best for
- Extended document analysis, research synthesis, and conversational tasks that need more context than GLM 4.7 but where inference speed is secondary to capability.
- Limitations
- Superseded by GLM 5.2 and later releases; newer models offer larger context windows (1M tokens) and improved reasoning, making this an interim choice for legacy integrations or cost-constrained deployments.
Input / 1M
$1.40
Output / 1M
$4.40
Cached input / 1M
$0.26
Context window
202K
Price history
Input (solid)Output (dashed)
Price change
- 30d
- in increased 45.1% out increased 45.1%
- 90d
- in increased 44.9% out increased 44.9%
- 1y
- in increased 42.9% out increased 42.9%
- Since launch
- in increased 42.9% out increased 42.9%
Snapshots
| Effective | Input | Output | Cached in | Note | Source |
|---|---|---|---|---|---|
| 28 Oct 2026 | $1.40 | $4.40 | $0.26 | Imported from OpenRouter | openrouter.ai |
| 27 Oct 2026 | $0.966 | $3.04 | $0.1794 | Imported from OpenRouter | openrouter.ai |
| 21 Oct 2026 | $1.40 | $4.40 | $0.26 | Imported from OpenRouter | openrouter.ai |
| 15 Oct 2026 | $0.966 | $3.04 | $0.1794 | Imported from OpenRouter | openrouter.ai |
| 14 Oct 2026 | $1.33 | $4.18 | $0.247 | Imported from OpenRouter | openrouter.ai |
| 7 Oct 2026 | $0.966 | $3.04 | $0.1794 | Imported from OpenRouter | openrouter.ai |
| 3 Oct 2026 | $1.40 | $4.40 | $0.26 | Imported from OpenRouter | openrouter.ai |
| 30 Sep 2026 | $0.9646 | $3.03 | $0.1791 | Imported from OpenRouter | openrouter.ai |
| 29 Sep 2026 | $0.9646 | $3.03 | $0.1791 | Imported from OpenRouter | openrouter.ai |
| 28 Sep 2026 | $0.9646 | $3.03 | $0.1791 | Imported from OpenRouter | openrouter.ai |
| 25 Sep 2026 | $0.9646 | $3.03 | $0.1791 | Imported from OpenRouter | openrouter.ai |
| 30 Aug 2026 | $0.966 | $3.04 | $0.1794 | Imported from OpenRouter | openrouter.ai |
| 25 Aug 2026 | $1.26 | $3.96 | $0.234 | Imported from OpenRouter | openrouter.ai |
| 15 Aug 2026 | $0.966 | $3.04 | $0.1794 | Imported from OpenRouter | openrouter.ai |
| 14 Aug 2026 | $1.40 | $4.40 | $0.26 | Imported from OpenRouter | openrouter.ai |
| 13 Aug 2026 | $0.952 | $2.99 | $0.1768 | Imported from OpenRouter | openrouter.ai |
| 12 Aug 2026 | $1.40 | $4.40 | $0.26 | Imported from OpenRouter | openrouter.ai |
| 11 Aug 2026 | $0.952 | $2.99 | $0.1768 | Imported from OpenRouter | openrouter.ai |
| 10 Aug 2026 | $0.952 | $2.99 | $0.1768 | Imported from OpenRouter | openrouter.ai |
| 5 Aug 2026 | $0.952 | $2.99 | $0.1768 | Imported from OpenRouter | openrouter.ai |
| 3 Jul 2026 | $0.966 | $3.04 | $0.1794 | Imported from OpenRouter | openrouter.ai |
| 30 Jun 2026 | $0.975 | $4.30 | — | Imported from OpenRouter | openrouter.ai |
| 25 Jun 2026 | $0.98 | $3.08 | $0.182 | Imported from OpenRouter | openrouter.ai |
| 21 Jun 2026 | $0.98 | $3.08 | $0.49 | Imported from OpenRouter | openrouter.ai |
| 11 Jun 2026 | $0.98 | $3.08 | $0.182 | Imported from OpenRouter | openrouter.ai |