Z
GLM 5.1OPEN
GLM 5.1 (Z.AI): live API pricing, context window and the best open-source alternatives, tracked daily by OpenSourceAI.tech.
Prices update automatically — checked hourly against provider list prices.
Benchmarks & performance
Independent benchmark scores for GLM 5.1, measured by Artificial Analysis. Higher is better. Measurement mode: Reasoning.
For the same budget, GLM 5.1 delivers 3.1 times more capability. Open weights also mean you can self-host it and pay nothing per token.
About this model
GLM 5.1 is an open-weight AI model by Z.AI. You can download and self-host it for free; the prices below are hosted-API list prices, tracked hourly, for when you prefer convenience over self-hosting.
Frequently asked questions
What is GLM 5.1?
GLM 5.1 is an AI language model from Z.AI. It is open-weight: you can download it and run it on your own hardware, for free. It scores 40.2 on the Artificial Analysis intelligence index.
Is GLM 5.1 free?
The weights are free and open — you can self-host GLM 5.1 and pay nothing per token. If you prefer a hosted API, list prices are $0.97 per million input tokens and $3.04 per million output tokens.
What is GLM 5.1 good at?
Independent benchmarks from Artificial Analysis give it GPQA 86.8%, Humanity's Last Exam 28%, Long Context Reasoning 62.3%, SciCode 43.8%, IFBench 76.3%, τ²-Bench 97.7%, τ-Bench Banking 11.5%, Terminal-Bench 61.8%, Terminal-Bench Hard 43.2%. It is particularly used for code generation.
Can I self-host GLM 5.1?
Yes. GLM 5.1 has open weights, so you can download it and run it on your own GPU or server with tools like Ollama, vLLM or llama.cpp — with no per-token cost.
Open-source alternatives
Depending on your workload, an open-weight model that you can self-host may cut costs dramatically or remove per-token pricing entirely. Our comparison pages put this model side by side with the strongest open-source contenders.