GLM 5.1 is Z.ai's foundation model with a 200K-token context window, positioned between the earlier GLM 5 and the newer reasoning-focused GLM 5.2.
- Strengths
- Handles long-context tasks and complex reasoning across documents and multi-turn conversations at scale.
- Best for
- Applications requiring extended context windows for document analysis, research synthesis, and reasoning-heavy workflows where GLM 5.2's reasoning overhead is unnecessary.
- Limitations
- Superseded by GLM 5.2 for specialized reasoning tasks and by GLM 5 Turbo for speed-critical agent-driven applications; not optimized for multimodal inputs or real-time inference.
Input / 1M
$0.966
Output / 1M
$3.04
Cached input / 1M
$0.1794
Context window
200K
Price history
Input (solid)Output (dashed)
Price change
- 30d
- in decreased 1.4% out decreased 1.4%
- 90d
- in decreased 1.4% out decreased 1.4%
- 1y
- in decreased 1.4% out decreased 1.4%
- Since launch
- in decreased 1.4% out decreased 1.4%
Snapshots
| Effective | Input | Output | Cached in | Note | Source |
|---|---|---|---|---|---|
| 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 |