How to Tap DeepSeek V4 Pro for Free via ZenMux — No Credit Card Required
DeepSeek's models rival top Western LLMs on many benchmarks, but paid API access can be a barrier for hobbyists and indie developers. This free route through ZenMux lowers that barrier to zero, making it a practical option for anyone building on a budget or evaluating DeepSeek's capabilities before committing to paid plans.
A practical walkthrough shows developers how to connect to DeepSeek V4 Pro's free tier without paying a cent. The method relies on ZenMux, a platform that provides API keys for free models including deepseek-v4-pro-free, deepseek-v4-flash-free, and GLM variants. The setup requires only a ZenMux account and optionally a local API forwarding tool like cc-switch or Cherry Studio.
The process is straightforward: register on ZenMux, create an API key with model restrictions set to the free models, then configure a local client to point at ZenMux's API endpoint. The guide includes screenshots for every step and warns about peak-hour slowdowns, token limits, and the importance of keeping API keys private.
A test conversation reveals the model identifies itself as "the latest version of DeepSeek" but not specifically DeepSeek-v4, suggesting the free tier may serve a newer but potentially less capable variant. Still, for personal use, prototyping, or API testing, the free access eliminates the usual paywall barrier.
The free tier's identity ambiguity — claiming to be the latest DeepSeek but not DeepSeek-v4 — suggests ZenMux may be routing to a different underlying model, which could affect reliability for production use.
This method effectively turns a third-party aggregator into a free proxy for DeepSeek, raising questions about how long such free access will last and whether it violates DeepSeek's terms of service.
The guide's popularity in the Chinese developer community signals strong demand for zero-cost access to frontier models, especially among developers who cannot easily pay with international credit cards.
The inclusion of GLM models alongside DeepSeek indicates ZenMux is positioning itself as a multi-model free hub, not just a DeepSeek proxy.