{
  "updated": "2026-10-28",
  "report_url": "https://freetier.tech/api/v1/reports",
  "category": {
    "id": "email",
    "name": "Transactional email",
    "description": "Send email from your app over an API or SMTP, such as signups, password resets and receipts.",
    "keywords": [
      "email",
      "smtp",
      "transactional email",
      "notifications",
      "mail"
    ],
    "count": 3,
    "url": "https://freetier.tech/api/v1/categories/email.json",
    "markdown": "https://freetier.tech/c/email.md",
    "page": "https://freetier.tech/c/email/"
  },
  "services": [
    {
      "id": "brevo",
      "name": "Brevo",
      "category": "email",
      "tagline": "Customer messaging platform with a transactional email API and SMTP relay alongside marketing email, SMS and CRM tools.",
      "website": "https://www.brevo.com",
      "pricing_url": "https://www.brevo.com/pricing/",
      "free_tier": {
        "kind": "always-free",
        "summary": "300 emails per day, shared between transactional email and campaigns.",
        "limits": [
          "300 emails per day (transactional and campaigns combined)",
          "100,000 contacts",
          "1,000 requests per second on the transactional send endpoint (POST /v3/smtp/email)",
          "100 requests per hour on API endpoints without a dedicated rate limit"
        ],
        "credit_usd": null,
        "commercial_use": true,
        "card_required": false
      },
      "gotchas": [
        "Brevo has to approve a new account before it can send; if sends fail with \"SMTP account is not yet activated\", request transactional activation through a support ticket from the account.",
        "The sender address must be verified (Brevo emails it a link) or its domain authenticated before you can send from it.",
        "The 300-per-day cap is shared with marketing campaigns, and only a paid plan removes it.",
        "Account, sender and domain API endpoints fall under the 100 requests/hour general limit.",
        "API keys are shown only once, when created."
      ],
      "setup": {
        "signup_url": "https://onboarding.brevo.com/account/register",
        "signup_methods": [
          "email"
        ],
        "human_steps": [
          "Sign up at https://onboarding.brevo.com/account/register with an email address and organization name, then verify the email.",
          "Create an API key at https://app.brevo.com/settings/keys/api.",
          "Verify a sender email address or authenticate your sending domain (DNS records) in Brevo."
        ],
        "agent_access": [
          {
            "method": "api-key",
            "install": "npm install @getbrevo/brevo",
            "command": null,
            "token_url": "https://app.brevo.com/settings/keys/api",
            "env_var": "BREVO_API_KEY",
            "notes": "Send the key in the `api-key` header; the SDKs take it as a constructor argument (Brevo's PHP guide reads it from BREVO_API_KEY)."
          }
        ],
        "verify": "curl -s https://api.brevo.com/v3/account -H \"api-key: $BREVO_API_KEY\"",
        "try_without_account": null
      },
      "docs": {
        "quickstart": "https://developers.brevo.com/docs/quickstart",
        "llms_txt": "https://developers.brevo.com/llms.txt"
      },
      "sources": [
        "https://www.brevo.com/pricing/",
        "https://www.brevo.com/pricing.md",
        "https://www.brevo.com/llms.txt",
        "https://www.brevo.com/free-smtp-server/",
        "https://www.brevo.com/features/email-api/",
        "https://www.brevo.com/products/transactional-email/",
        "https://help.brevo.com/hc/en-us/articles/115000188150-Troubleshooting-Issues-with-Brevo-SMTP",
        "https://developers.brevo.com/docs/quickstart",
        "https://developers.brevo.com/docs/api-key-authentication",
        "https://developers.brevo.com/docs/api-limits",
        "https://developers.brevo.com/docs/send-a-transactional-email",
        "https://developers.brevo.com/docs/sender-creation-and-management",
        "https://developers.brevo.com/guides/node-js",
        "https://developers.brevo.com/guides/php",
        "https://developers.brevo.com/llms.txt"
      ],
      "last_verified": "2026-10-28",
      "sponsored": false,
      "links": {
        "page": "https://freetier.tech/s/brevo/",
        "markdown": "https://freetier.tech/s/brevo.md",
        "json": "https://freetier.tech/api/v1/services/brevo.json"
      }
    },
    {
      "id": "mailgun",
      "name": "Mailgun",
      "category": "email",
      "tagline": "Email API and SMTP relay for sending, receiving and tracking email.",
      "website": "https://www.mailgun.com",
      "pricing_url": "https://www.mailgun.com/pricing/",
      "free_tier": {
        "kind": "always-free",
        "summary": "100 emails per day with 1 custom sending domain and 1-day log retention.",
        "limits": [
          "100 emails per day",
          "1 custom sending domain",
          "2 API keys",
          "1-day log retention",
          "1 inbound route",
          "1 user per account"
        ],
        "credit_usd": null,
        "commercial_use": null,
        "card_required": false
      },
      "gotchas": [
        "Account activation requires verifying your email and a mobile number by SMS; VoIP, virtual and landline numbers are not accepted.",
        "The built-in sandbox domain only delivers to up to 5 authorized recipients, who must each confirm by email; verify a custom domain to send to anyone.",
        "Domains created in the EU region must use https://api.eu.mailgun.net instead of https://api.mailgun.net.",
        "Domain sending keys can only send messages; listing or managing domains needs an account API key."
      ],
      "setup": {
        "signup_url": "https://signup.mailgun.com/new/signup",
        "signup_methods": [
          "email"
        ],
        "human_steps": [
          "Sign up at https://signup.mailgun.com/new/signup.",
          "Activate the account by verifying your email address and a mobile phone number (SMS code).",
          "Create an API key at https://app.mailgun.com/settings/api_security.",
          "Add your sending domain's DNS records at your DNS provider, or add yourself as an authorized recipient to test with the sandbox domain."
        ],
        "agent_access": [
          {
            "method": "api-key",
            "install": null,
            "command": null,
            "token_url": "https://app.mailgun.com/settings/api_security",
            "env_var": "MAILGUN_API_KEY",
            "notes": "HTTP Basic auth with username `api`; the official MCP server reads MAILGUN_API_KEY (and MAILGUN_API_REGION=eu for EU accounts)."
          }
        ],
        "verify": "curl -s --user \"api:$MAILGUN_API_KEY\" https://api.mailgun.net/v4/domains",
        "try_without_account": null
      },
      "docs": {
        "quickstart": "https://documentation.mailgun.com/docs/mailgun/quickstart",
        "llms_txt": "https://documentation.mailgun.com/llms.txt"
      },
      "sources": [
        "https://www.mailgun.com/pricing/",
        "https://www.mailgun.com/features/email-api/",
        "https://help.mailgun.com/hc/en-us/articles/203068914-What-does-the-Free-plan-offer",
        "https://help.mailgun.com/hc/en-us/articles/37182933150491-Account-Activation",
        "https://help.mailgun.com/hc/en-us/articles/217531258-Authorized-Recipients",
        "https://documentation.mailgun.com/docs/mailgun/quickstart",
        "https://documentation.mailgun.com/docs/mailgun/user-manual/domains/domains-sandbox",
        "https://documentation.mailgun.com/docs/mailgun/api-reference/api-overview",
        "https://documentation.mailgun.com/docs/mailgun/api-reference/mg-auth",
        "https://documentation.mailgun.com/docs/mailgun/user-manual/api-key-mgmt/rbac-mgmt",
        "https://documentation.mailgun.com/docs/mailgun/api-reference/send/mailgun/domains/get-v4-domains",
        "https://documentation.mailgun.com/docs/mailgun/mcp",
        "https://documentation.mailgun.com/docs/mailgun/sdk/nodejs_sdk",
        "https://www.mailgun.com/legal/terms/",
        "https://documentation.mailgun.com/llms.txt"
      ],
      "last_verified": "2026-10-28",
      "sponsored": false,
      "links": {
        "page": "https://freetier.tech/s/mailgun/",
        "markdown": "https://freetier.tech/s/mailgun.md",
        "json": "https://freetier.tech/api/v1/services/mailgun.json"
      }
    },
    {
      "id": "resend",
      "name": "Resend",
      "category": "email",
      "tagline": "Email API for sending transactional and marketing email, with SDKs, SMTP relay, inbound email and webhooks.",
      "website": "https://resend.com",
      "pricing_url": "https://resend.com/pricing",
      "free_tier": {
        "kind": "always-free",
        "summary": "3,000 transactional emails per month, capped at 100 per day, with up to 3 verified domains.",
        "limits": [
          "3,000 transactional emails per month",
          "100 emails per day (UTC calendar day)",
          "3 verified domains",
          "1 webhook endpoint",
          "30-day data retention",
          "1,000 marketing contacts",
          "10 API requests per second per team"
        ],
        "credit_usd": null,
        "commercial_use": null,
        "card_required": false
      },
      "gotchas": [
        "Received (inbound) emails and every To, CC and BCC recipient count against the daily and monthly quota.",
        "Until a domain is verified you can only send test emails from onboarding@resend.dev to your own account address; other recipients get a 403.",
        "API keys with \"Sending access\" can only send email; creating and verifying domains needs a \"Full access\" key.",
        "Going over the quota returns a 429 (daily_quota_exceeded or monthly_quota_exceeded); the daily quota resets at midnight UTC.",
        "A domain's region and return path can't be changed after it is created."
      ],
      "setup": {
        "signup_url": "https://resend.com/signup",
        "signup_methods": [
          "google",
          "github",
          "email"
        ],
        "human_steps": [
          "Sign up at https://resend.com/signup (Google, GitHub or email).",
          "Create an API key at https://resend.com/api-keys (Full access if the agent will set up domains), or approve the MCP server's OAuth login.",
          "Add the DNS records Resend lists for your sending domain at your DNS provider, unless the agent can edit DNS."
        ],
        "agent_access": [
          {
            "method": "api-key",
            "install": "npm install -g resend-cli",
            "command": null,
            "token_url": "https://resend.com/api-keys",
            "env_var": "RESEND_API_KEY",
            "notes": "The Resend CLI and local MCP server read RESEND_API_KEY; `resend login` stores a pasted key instead. The key is shown only once."
          },
          {
            "method": "oauth",
            "install": null,
            "command": "claude plugin install resend@claude-plugins-official",
            "token_url": null,
            "env_var": null,
            "notes": "Adds the hosted MCP server (https://mcp.resend.com/mcp); run /mcp and log in through the browser. For Codex, `codex mcp add resend --url https://mcp.resend.com/mcp`."
          }
        ],
        "verify": "resend doctor",
        "try_without_account": null
      },
      "docs": {
        "quickstart": "https://resend.com/docs/introduction",
        "llms_txt": "https://resend.com/llms.txt"
      },
      "sources": [
        "https://resend.com/pricing",
        "https://resend.com/pricing.md",
        "https://resend.com/docs/knowledge-base/account-quotas-and-limits",
        "https://resend.com/docs/api-reference/rate-limit",
        "https://resend.com/changelog/three-domains-on-the-free-tier",
        "https://resend.com/legal/terms-of-service",
        "https://resend.com/docs/knowledge-base/403-error-resend-dev-domain",
        "https://resend.com/docs/create-an-api-key",
        "https://resend.com/docs/dashboard/api-keys/introduction",
        "https://resend.com/docs/cli",
        "https://resend.com/docs/mcp-server",
        "https://resend.com/docs/ai-onboarding",
        "https://resend.com/setup.md",
        "https://resend.com/auth.md",
        "https://resend.com/signup",
        "https://resend.com/docs/introduction",
        "https://resend.com/llms.txt"
      ],
      "last_verified": "2026-10-28",
      "sponsored": false,
      "links": {
        "page": "https://freetier.tech/s/resend/",
        "markdown": "https://freetier.tech/s/resend.md",
        "json": "https://freetier.tech/api/v1/services/resend.json"
      }
    }
  ]
}