Resend

Resend came out of Y Combinator's Winter 2023 batch and launched publicly that June, built by developers who had already built React Email, the open source library for writing email templates as React components. That lineage shows in the product: templates can be written as JSX, previewed locally, and sent through SDKs for Node, Python, Ruby, and several other languages, with a clean API for one-off transactional sends and batch sends alike. Webhooks cover delivery, bounce, and complaint events, and the dashboard shows per-email logs without much clutter.

Billing is by email volume. The free plan allows 3,000 emails a month with a 100-per-day cap, one custom domain, and basic analytics, genuinely usable for a side project or an early-stage app rather than a crippled trial. The Pro plan starts around $20 a month for 50,000 emails, though 2026 brought a pricing restructure that roughly doubled some of the higher-volume tiers, worth checking against the current pricing page before committing to a plan you expect to outgrow. Resend fits a team building in React or Next.js that wants a fast setup and doesn't need the enterprise deliverability tooling of an older, larger provider.