Maths is your friend. If you attract 1000 subscribers and convert 5% at $5 per month, you can expect to earn $250 per month. If you convert 1000 subscribers from a much more extensive list at the same rate, you can expect to earn $5000 a month. Maths is your friend. Luke O’Neill earns over $100000 per year from Welcome to Hell World! However, he is a high-profile writer. It’s hard to make money on Substack without an audience or online marketing skills.