[LoRA Training] Auto-caption generator recommendation?

Hi Guys! I'm kinda new in image generation. I'm trying to train a character image LoRA with multiple image references. And I believe captions for each image are needed right? If I have, let's say 30 or images, it'll be tiring to put caption for each. Would you recommend any great LoRA auto-caption generator that is free to use for multiple images all at once? By the way, i'm