# Help using cuDNN in Julia
**URL:** https://discourse.julialang.org/t/help-using-cudnn-in-julia/126232
**Category:** Machine Learning
**Tags:** cuda, cudnn
**Created:** [February 24, 2025, 5:20am UTC](https://discourse.julialang.org/t/help-using-cudnn-in-julia/126232 "2025-02-24T05:20:55Z")
**Posts on this page:** 2
**Page:** 1
### Author:  [@notGiGi](https://discourse.julialang.org/u/notGiGi)
#### Post date: [February 24, 2025, 5:20am UTC](https://discourse.julialang.org/t/help-using-cudnn-in-julia/126232/1 "2025-02-24T05:20:55Z")
Hello, everyone. I’m trying to use cuDNN in Julia, but so far it’s not working as expected. I’m very confused. It is supposed to be included in CUDA.jl so that I can use `using CUDA.CUDNN`, but when I do that, I get the error:
UndefVarError: `CUDNN` not defined in `CUDA`
Suggestion: check for spelling errors or missing imports.
Now I think I’ve made a mess because I added the package named cuDNN.jl and also tried to download it from the NVIDIA site, but so far I still can’t use cuDNN in my Julia code.
Any help or guidance would be greatly appreciated!
[https://discourse.julialang.org/t/cudnn-in-julia/84330/2?u=notgigi](https://discourse.julialang.org/t/cudnn-in-julia/84330/2)
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### Author:  [@christiangnrd](https://discourse.julialang.org/u/christiangnrd)
#### Post date: [February 25, 2025, 5:02pm UTC](https://discourse.julialang.org/t/help-using-cudnn-in-julia/126232/2 "2025-02-25T17:02:52Z")
cuDNN.jl was split into a separate package (that lives in the CUDA.jl repository) so to use it you must now use `using cuDNN` after adding it to your envoronment just like you would with CUDA.jl