GLM-4.5-Air vs Grok Build 0.1
GLM-4.5-Air (Z.ai) and Grok Build 0.1 (xAI) side by side: what each costs per million tokens through Rapid Router, how much context each takes, what each supports, and where independent benchmarks place them. Same API, same key; switching is a one-string change.
| GLM-4.5-Air | Grok Build 0.1 | |
|---|---|---|
| Input price per 1M | $0.030 | $1.00 |
| Output price per 1M | $0.140 | $2.00 |
| Context window | 131K tokens | 256K tokens |
| Max output | 98K tokens | 256K tokens |
| Input types | text | text, image, pdf |
| Capabilities | tools, reasoning | tools, JSON, vision, reasoning |
| Author | Z.ai | xAI |
| LMArena Overall | 1384 | — |
| LMArena Coding | 1397 | — |
| LMArena Math | 1396 | — |
| LMArena Creative writing | 1343 | — |
| LMArena Instruction following | 1354 | — |
| LMArena Hard prompts | 1379 | — |
| Humanity's Last Exam | 8.1% | — |
Scores from LMArena and Epoch AI, as published; a blank cell means not measured there.
What a month costs on each
| Workload | GLM-4.5-Air | Grok Build 0.1 |
|---|---|---|
| Chatbot month (15M in, 4M out) | $1.01 | $23.00 |
| RAG month (40M in, 3M out) | $1.62 | $46.00 |
| Coding month (60M in, 10M out) | $3.20 | $80.00 |
On a typical 75/25 input-output mix, GLM-4.5-Air costs less (about 95% less than Grok Build 0.1). Grok Build 0.1 takes the longer prompt at 256K tokens. Try your own numbers in the cost calculator.
Call either one
curl https://rapidrouter.ai/api/v1/chat/completions \
-H "Authorization: Bearer $RAPIDROUTER_API_KEY" \
-H "Content-Type: application/json" \
-d '{"model": "z-ai/glm-4.5-air", "messages": [{"role": "user", "content": "Hello"}]}'
# the other one: change the model string
-d '{"model": "x-ai/grok-build-0.1", ...}'Common questions
Which is cheaper, GLM-4.5-Air or Grok Build 0.1?
GLM-4.5-Air is cheaper on a typical mix of 75% input and 25% output tokens, by about 95%. Through Rapid Router both are billed at the provider list price per million tokens.
Which has the larger context window?
Grok Build 0.1, at 256K tokens. GLM-4.5-Air offers 131K tokens.
Can I switch between GLM-4.5-Air and Grok Build 0.1 without changing code?
Yes. Both are callable at https://rapidrouter.ai/api/v1 with the same OpenAI-compatible request; only the model string changes (z-ai/glm-4.5-air or x-ai/grok-build-0.1).
How do I pay for GLM-4.5-Air or Grok Build 0.1?
Top up a Rapid Router balance by card in US dollars, and both models debit that balance per request.
More GLM models: Z.ai API pricing · More Grok: xAI API pricing