A great tool for standalone denoise your renders PNG or JPG sequences supported.

https://github.com/DeclanRussell/NvidiaAIDenoiser

You will need to download Nvidia’s OPTIX and CUDA SDKs from the dev site.

“You will require an Nvidia driver of at least 465.84 or higher and an Nvidia GPU of Maxwell architecture or newer to use the OptiX denoiser.“