Model comparison
GLM 5.1 vs GLM 5.1 Fast
Compare GLM 5.1 and GLM 5.1 Fast: input/output $/Mtoken, context window, modalities, and license. OpenRouter-synced pricing.
Accounts
GLM 5.1
Flagship GLM model for hybrid reasoning, coding, and agentic engineering
Accounts
GLM 5.1 Fast
Efficient GLM model for fast reasoning, coding, and agent workflows
| Metric | GLM 5.1 | GLM 5.1 Fast |
|---|---|---|
| Provider | Accounts | Accounts |
| Context window | 202,800 | 202,800 |
| Input $/Mtok | $1.40 | $2.80 |
| Output $/Mtok | $4.40 | $8.80 |
| Modalities | text | text |
| License | open-weights | open-weights |
Quick take
On input price, GLM 5.1 is cheaper at $1.40/Mtok. For context window, GLM 5.1 leads with 202,800 tokens.
Pick based on your workload: high-volume cheap inference vs long-document / agent loops. Enterprise DNA can wire either model into Omni with evals, secrets, and job orchestration.