Email for developers.
Resend is an email API for sending transactional and marketing email. It covers the sending path end to end - a REST API and SMTP relay, official SDKs across a dozen languages, domain authentication, webhooks for delivery events, contact and segment management, and a visual editor for broadcasts. It is unusually well instrumented for agent use: a published OpenAPI 3.0 specification, a hosted OAuth-protected MCP server, a CLI, and agent skills covering its own API and email best practice.
| Plan | Price | Included | Notable |
|---|---|---|---|
| Free | Not published in the retrieved page - see note | 100 emails/day, 1 custom domain, 1 webhook endpoint, 30-day data retention, 5 AI credits/mo | RESTful API, SMTP relay and official SDKs, Inbound emails, scheduled emails and batch sending, Open tracking, link tracking and React Email |
| Pro | Not published in the retrieved page - see note | No daily limit, 10 custom domains, 10 webhook endpoints, 30-day data retention, 100 AI credits/mo | Everything in Free, No daily sending limit, 10 custom domains and 10 webhook endpoints |
| Scale | Not published in the retrieved page - see note | No daily limit, 1,000 custom domains, 10 webhook endpoints, 30-day data retention, 500 AI credits/mo | Everything in Pro, 1,000 custom domains, Dedicated IPs available with add-on, including dedicated IP warming |
| Enterprise | Not published in the retrieved page - see note | No daily limit, flexible custom domains, flexible webhook endpoints, flexible data retention, flexible AI credits | Everything in Scale, Flexible custom domains, webhook endpoints and data retention, Dedicated IPs available with add-on |
| Dedicated IPs (add-on) | $30 / mo | Available to customers exceeding 3,000 emails sent per day on the Scale plan | Warmed, monitored and autoscaled based on your utilisation |
Checked 2026-08-07 against their pricing page. Vendors change pricing without notice.
An email infrastructure provider positioned against Mailgun, SendGrid and Postmark on developer experience. The distinguishing choice is how completely it is machine-readable: the OpenAPI spec is published at a stable URL in both JSON and YAML, the changelog and pricing are available as markdown, an MCP discovery document sits at a well-known path, and the pricing page itself carries a link addressed to AI agents. The API surface is broader than "send an email" suggests - the spec's tags cover Emails, Domains, API Keys, Contacts, Segments, Topics, Contact Properties, Templates, Broadcasts, Receiving Emails, Webhooks, Automations, Events and Logs, with Audiences marked deprecated in favour of Segments.
Developers and product teams that need to send email from an application - the vendor's own framing is "a team of engineers who love building tools for other engineers", and the entry point everywhere is a code snippet. The tiering runs from a free plan with a 100-email daily limit up to a flexible Enterprise plan, so the range genuinely spans a side project to a high-volume sender.
This is an API-first product, and the marketing side of it is thinner than a dedicated marketing platform: there is a broadcast editor, segments and topics, but nothing we retrieved suggests visual journey building or lifecycle campaign orchestration, so a marketing team wanting to design multi-step nurture flows without engineering support is buying the wrong tool. Two concrete limits are worth checking against your case before committing. Data retention is 30 days on Free, Pro and Scale alike - only Enterprise is flexible - so if you need email history beyond a month for audit or support purposes, you are exporting it yourself or negotiating an Enterprise contract. And dedicated IPs are a $30/month add-on that the vendor restricts to customers exceeding 3,000 emails per day on the Scale plan, so a lower-volume sender with a reputation-isolation requirement cannot simply buy one. Support tiering is also sharp: Slack support and an urgent-response SLA exist only on Scale and Enterprise.
No curated rival set covers this tool yet, so these are simply other tools in the same architectural layer and product form. Treat it as a starting point, not a shortlist.
Yes.
We can give you the plan structure but not the prices. The only price we can report is the dedicated IP add-on at $30/month. The Free plan's 100-emails-per-day limit and "start for free" framing are documented. Check the live pricing page for current figures.
Yes, and both hosted and self-hosted. The MCP page describes tools spanning send/list/get/cancel/update/batch email, reading inbound email and attachments, contacts, topics, contact properties, broadcasts, domains, segments, API keys and webhooks.
30 days on Free, Pro and Scale alike. Only Enterprise is listed as flexible. If you need longer retention for audit or support, plan to export or negotiate.
Only conditionally. It is a $30/month add-on, and the pricing page states it is available to customers exceeding 3,000 emails sent per day on the Scale plan. Resend warms, monitors and autoscales it. Below that volume you are on what the vendor calls pristine shared IPs.
Yes. Webhook events for delivered, opened, clicked, bounced and complained can all be simulated.
Yes - the OpenAPI spec has a Receiving Emails tag for retrieving and managing received emails and attachments, inbound emails appear on every pricing tier, and the MCP page lists reading inbound email and downloading attachments as agent-accessible operations.
The changelog is public and active. Entries in July and August 2026 include template folders, email suppressions manageable from dashboard and API, a Codex plugin bundling the MCP server and Resend skills, a GitHub secret scanner that detects and revokes exposed API keys automatically, OAuth 2.1 with PKCE, a one-click Claude connector, Message-ID on all email webhooks and GET endpoints, the remote MCP server, and CSV contact import with AI column mapping.
Its llms.txt says yes - it enumerates five skills covering core API usage, React Email, email best practices, the CLI, and an agent email inbox, along with a skills-discovery document at a well-known path.
Ask the vendor for the canonical address.
This page tells you whether Resend fits. Cheetah builds and runs the system it goes into — enrichment, sequencing, CRM and the joins between them.
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