If you're looking to boost your YouTube subscriber count without spending any money, there are several free strategies you can try. First, create high-quality, engaging content that viewers will want to subscribe to. Collaborate with other YouTubers in your niche to reach a wider audience. Promote your channel on social media and engage with your viewers by responding to comments and messages. Utilize keywords and tags to make your videos more discoverable in search results. Finally, consider hosting giveaways or contests to incentivize viewers to subscribe to your channel. With dedication and persistence, you can increase your YouTube subscriber count for free.