GLM-5.1 API pricing
Official GLM (Z.ai) list price, last checked Oct 29, 2026. Updated Oct 29, 2026.
GLM-5.1 costs $1.40 per 1M input tokens and $4.40 per 1M output tokens, cached input at $0.26, per GLM (Z.ai)'s official pricing page (checked Oct 29, 2026). It's a premium-priced model: number 54 of 77 by blended price ($2.15 per 1M tokens at a 3 to 1 input to output mix). On LMArena's Code Arena it ranks #32 of 50 models we price (relative score 0 out of 100). Cheaper pick: MiMo-V2.6 Flash scores 36 against 0 on the same board at $0.175 blended, 12.3x less.
GLM-5.1 price per million tokens
| GLM-5.1 price per million tokens | USD |
|---|---|
| Input | $1.40 |
| Cached input | $0.26 |
| Output | $4.40 |
| Blended, 3 parts input to 1 part output | $2.15 |
| Context window | Not listed |
GLM (Z.ai) lists one flat rate for GLM-5.1: no long-prompt surcharge or tier is shown on the pricing page we checked.
What GLM-5.1 costs for real work
List-price estimates for a month, no discounts. Our math, not a quote: change the token counts in the plan vs API calculator.
| Workload | Tokens a month | GLM-5.1 | GPT-6.1 Terra | DeepSeek V4.1 Flash |
|---|---|---|---|---|
| Light: a side project or personal assistant | 2M in, 0.5M out | $5.00 | $4.50 | $1.20 |
| Medium: a small team or one product feature | 20M in, 5M out | $50.00 | $45.00 | $12.00 |
| Heavy: a production app | 200M in, 50M out | $500 | $450 | $120 |
| Medium with 80% of input cached | 20M in (16M cached), 5M out | $31.76 | $29.80 | $7.30 |
How GLM-5.1 ranks on LMArena
Relative score: 100 is the top model we price on that board. Rank is among the models in our price table, not the full leaderboard.
| Board | Rank | Score /100 |
|---|---|---|
| Coding (Code Arena) | #32 of 50 | 0 |
| Chat (Text Arena) | #23 of 51 | 0 |
| Creative writing (Text Arena creative writing) | #20 of 51 | 1 |
| Roleplay and characters (Text Arena multi-turn) | #15 of 51 | 3 |
| Reasoning and math (Text Arena math) | #25 of 51 | 0 |
Closest rivals to GLM-5.1
The models nearest in price, other makers first. Ranks are on Code Arena, where we have them.
| Model | In / out | Blended | Verdict |
|---|---|---|---|
| GPT-6.1 Terra | $1 / $5 | $2 | GPT-6.1 Terra wins on both. Compare |
| Muse Spark 1.3 | $1.25 / $4.25 | $2 | Muse Spark 1.3 wins on both. Compare |
| DeepSeek V4 Pro | $1.32 / $3.96 | $1.98 | DeepSeek V4 Pro wins: cheaper, same score. Compare |
| Grok 4.3 | $1.25 / $2.50 | $1.56 | Grok 4.3 wins: cheaper, same score. Compare |
Cheaper alternatives to GLM-5.1
At least 40% cheaper blended, best LMArena score first.
| Model | In / out | Blended | Verdict |
|---|---|---|---|
| DeepSeek V4.1 Flash | $0.30 / $1.20 | $0.525 | DeepSeek V4.1 Flash wins on both. Compare |
| MiMo-V2.6 Flash | $0.14 / $0.28 | $0.175 | MiMo-V2.6 Flash wins on both. Compare |
| Hunyuan Hy4 Preview | $0.834 / $2.50 | $1.25 | Hunyuan Hy4 Preview wins on both. Compare |
More from GLM (Z.ai)
- GLM-5.3$1.40 in, $4.40 out per 1M
- GLM-5.2$1.40 in, $4.40 out per 1M
- GLM-5$1 in, $3.20 out per 1M
- GLM-4.7$0.60 in, $2.20 out per 1M
- GLM-4.6$0.60 in, $2.20 out per 1M
FAQ
How much does the GLM-5.1 API cost per million tokens?
$1.40 per 1M input tokens and $4.40 per 1M output tokens, plus $0.26 per 1M for cached input, as of Oct 29, 2026. A typical 3 to 1 input to output mix works out to $2.15 per 1M tokens.
Does GLM-5.1 charge more for long prompts?
No. GLM (Z.ai) lists a single rate on its pricing page.
Is GLM-5.1 cheaper than GPT-6.1 Terra?
No. A medium month (20M input and 5M output tokens) costs $50.00 on GLM-5.1 and $45.00 on GPT-6.1 Terra at list price. On Code Arena, GLM-5.1 ranks #32 and GPT-6.1 Terra #11.
How does GLM-5.1 rank on LMArena?
On Code Arena it is #32 of 50 models we price, with a relative score of 0 out of 100. It ranks on 5 of 8 boards we track.
What is a cheaper alternative to GLM-5.1?
DeepSeek V4.1 Flash costs $0.30 in and $1.20 out per 1M tokens, about 4.1x less blended, and scores 46 on Code Arena against 0 for GLM-5.1.
Where does this GLM-5.1 price come from?
From GLM (Z.ai)'s official pricing page, which we check every day. This page was last checked Oct 29, 2026.