GLM-5.1
Z.AIOpen weightsMITReleased Apr 7, 2026
GLM-5.1 has no arena.ai Agents result yet, so on our leaderboard it is listed after models that do. GLM-5.1 ranks #54 on the LMArena Text leaderboard (style control) with an Arena score of 1465.2 (±3.6, 62,889 votes). Artificial Analysis Intelligence Index: 26.1. API price: $1.29 input / $4.07 output per 1M tokens. Context: 205K. Nearest rivals: Grok 4.5 (1465.7) above and DeepSeek V4 Pro (1464.6) below.
Quick answer
- Agents leaderboard
- No result yet
- Text (LMArena)
- #54 · 1465.2
- 17NAS overall
- #59 of 84
- API price (in / out)
- $1.29 / $4.07 per 1M tokens
- Closest rival
- Grok 4.5 · 1465.7
- Cheaper alternative
- MiMo-V2.6-Pro: Text 1479.2, output $0.87 (79% cheaper)
- Data updated
- Oct 16, 2026 · synced daily
Sources: arena.ai, LMArena, Artificial Analysis, OpenRouter
Key metrics
Reasoning effort comparison
Artificial Analysis measurements per reasoning effort of the same model| Effort | Intelligence | Coding | tok/s | TTFT (s) | First answer (s) |
|---|---|---|---|---|---|
| reasoningUsed in table | 26.1 | 55.8 | – | – | – |
| non-reasoning | 24.2 | – | – | – | – |
Models ranked nearby
Sorted by Arena score| # | Model | Arena | Intel. | Output $ | tok/s |
|---|---|---|---|---|---|
| 39 |  MiMo V2.5 Pro | 1467.3 | 26.0 | $0.87 | – |
| 40 |  GPT-5.6 Terra | 1466.4 | 42.1 | $12.00 | 116 |
| 41 |  Grok 4.5 | 1465.7 | 38.8 | $6.00 | – |
| 42 | GLM-5.1This page | 1465.2 | 26.1 | $4.07 | – |
| 43 |  DeepSeek V4 Pro | 1464.6 | 36.0 | $3.96 | 93 |
| 44 |  Claude Sonnet 5 | 1461.1 | 38.2 | $10.00 | – |
| 45 |  Kimi K2.6 | 1460.8 | 27.0 | $4.00 | – |
More from Z.AI
| # | Model | Arena | Intel. | Output $ | tok/s |
|---|---|---|---|---|---|
| 25 | GLM-5.3 | 1478.5 | 44.8 | $4.40 | 71 |
| 28 | GLM-5.2 | 1475.9 | 33.7 | $4.40 | – |
| 34 | GLM-5.3 Flash | 1473.8 | 41.8 | $0.50 | 63 |
Pricing
- Official API list price: $1.29 input and $4.07 output per 1M tokens (USD).
- At a typical 3:1 input-to-output ratio, the blended cost is about $1.98 per 1M tokens.
- Among 79 models with an output price, it is the #34 cheapest.
- The cheapest OpenRouter route charges $0.97 input / $3.04 output.
Sources & methodology
GLM-5.1 has no arena.ai Agents result yet, so on our leaderboard it is listed after models that do.
- arena.ai Agents — agent task success rate, 95% interval, sessions and rank (via the public Hugging Face dataset, CC BY 4.0).
- LMArena — Arena score (Text leaderboard with style control, the same view arena.ai shows by default), 95% confidence interval, votes and rank.
- Artificial Analysis — Intelligence / Coding Index, output speed and latency (medians).
- OpenRouter — Route prices, context length and listing date.
Arena scores use the Bradley-Terry model (not Elo); ± is the half-width of the 95% confidence interval. Latency figures are Artificial Analysis medians; for reasoning models, time to first token and to first answer include the thinking phase. Data syncs daily at 14:20 (UTC+8).
Limits: Arena scores come from anonymous users voting on chats, so they reflect conversational preference rather than agent or coding benchmarks; with few votes the interval is wide and ranks move. Prices and speeds change as providers update them.
FAQ
What rank is GLM-5.1 right now?
GLM-5.1 is #42 on our leaderboard of 69 scored models (Arena score 1465.2); its raw LMArena rank is #54.
What does GLM-5.1 cost via API?
Input $1.29 / output $4.07 per 1M tokens (official API list price; the OpenRouter quote when no official price is available). At a typical 3:1 input-to-output ratio, the blended cost is about $1.98 per 1M tokens.
How close is GLM-5.1 to the models ranked next to it?
It is 0.5 points behind Grok 4.5 (1465.7) and 0.6 points ahead of DeepSeek V4 Pro (1464.6); gaps smaller than the confidence interval (±3.6) are not significant.
Is GLM-5.1 open source? Can it be self-hosted?
GLM-5.1 is an open-weights model (license: MIT); you can download the weights and self-host.
What is the context length of GLM-5.1?
205K (204,800 tokens, as listed on OpenRouter).
GLM-5.1 vs Grok 4.5: which is better?
On the LMArena Text leaderboard GLM-5.1 scores 1465.2 and Grok 4.5 scores 1465.7 (a 0.5-point gap, within the confidence interval, so not significant). On price, GLM-5.1 costs $4.07 and Grok 4.5 $6.00 per 1M output tokens.
Is there a cheaper model close to GLM-5.1?
Yes: MiMo-V2.6-Pro scores 1479.2 on the Text leaderboard (GLM-5.1: 1465.2) and costs $0.87 per 1M output tokens, about 79% less than GLM-5.1 ($4.07).
Where does the GLM-5.1 data come from and how often is it updated?
Agent success rates come from the arena.ai Agents leaderboard (CC BY 4.0), Text scores from LMArena, intelligence and speed from Artificial Analysis, and prices and context from official list prices and OpenRouter. 17NAS syncs daily at 06:20 UTC; this page was last updated Oct 16, 2026.