Send receipts, password resets and campaigns from your own domain
Transactional email goes out with one API call. Campaigns and automated sequences are built in the dashboard on the same contact list. The first 5,000 sends each month are free.

POST /v1/send { "to": "tolu@koracoffee.com", "template": "welcome_onboarding", "variables": { "name": "Tolu" } } // → { "id": "msg_8f2a", "status": "queued" }
Transactional mail, campaigns and automations share one contact list
- Transactional sends
- Receipts, one-time codes, password resets and alerts go out with one POST to /v1/send. Idempotency keys stop a retried request from sending the same code twice.
- Deliverability
- We give you the SPF, DKIM and DMARC records for your domain, and pace sending to each mail provider, backing off when one pushes back, so a new address builds its reputation safely. Bounces, complaints and unsubscribes go on a suppression list automatically.
- Campaigns and templates
- Design in the drag-and-drop editor or paste your own HTML. Templates take variables and are shared with your team. Each campaign shows its opens and clicks as they come in.
- Automations
- Build welcome series, re-engagement and dunning flows from waits, sends and branches on whether someone opened or clicked the last email. A flow starts when someone joins a list, when your product posts an event to /v1/events, when someone clicks a campaign, when someone leaves a campaign unopened, or when a rewards member earns points, reaches a tier or redeems a reward.
- Contacts, lists and segments
- Import contacts in bulk or add them from your signup code. Lists and segments keep each contact's consent state, and every send checks it before going out.
- Tracking and webhooks
- Every message has a timeline you can query, the same events arrive by webhook as they happen, and the dashboard shows totals across your sends.
- AI agents
- Connect Claude or another MCP client to api.startupaid.org/mcp and it can send email and add contacts on your account.
AI marketing on the same list
Set a goal for the month and send purchases and signups to /v1/events to see which emails produced them. Try two subject lines on part of a list and send the one with more opens to the rest. Or describe a launch and get a dated plan across email, social and video, with each piece drafted and ready to schedule.
More about AI marketing →The main endpoints
/v1/sendSend one transactional email from a template or raw HTML, with an idempotency key and per-message tracking./v1/campaignsSend a campaign to a list or segment. Opens, clicks and unsubscribes are recorded for you./v1/audiences/:id/contacts/importAdd contacts to a list in bulk with a JSON body of { contacts: [...] }. Invalid addresses and duplicates are skipped, and the reply counts what was added and skipped./v1/messages/:idGet a message's delivery timeline: delivered, opened, clicked, bounced or complained.Email FAQ
Yes. Receipts, codes and newsletters go through the same API and dashboard, and marketing mail carries a one-click unsubscribe header.
We pace sending to each mail provider while a new address builds its reputation, and every message is signed for your domain. Bounces, complaints and unsubscribes are added to a suppression list automatically, and the dashboard shows your sending health.
No. Templates, campaigns and automations can all be built in the dashboard. If you'd rather send from your backend, the REST API covers the same things and the docs have copy-paste examples.
There are five triggers: someone joins a list, your product posts an event to /v1/events, someone clicks a given campaign, someone doesn't open a campaign in time, or a rewards member does something such as reaching a tier. Inside a flow you can add waits and branches. For example: wait a day, then send a different email depending on whether they clicked.
The first 5,000 emails each month are free and need no card. Paid plans include more emails each month, starting with 100,000 on Starter for $15 a month. Plans are sized by emails sent, so storing contacts you rarely email costs nothing. Email is its own subscription, on the same account and API key as push, currency and the other products.
The other products on the same account
They share one API key, one dashboard and one event stream, so adding one later doesn't mean another vendor or another integration.
- AI ReceptionistAnswers your phone and your website chat from your own facts, and puts customers through to you when they need a person.
- Push MessagingiOS, Android and web push from one send call, using your own keys. Free, with no volume cap.
- Currency ConversionRates for 230+ currencies across fiat, crypto and metals, with your own spread and the rate's timestamp on each conversion.
- Social AutomationSchedule posts to X, LinkedIn, Threads, Instagram, Facebook, YouTube and TikTok, or publish them from your own code.
- AI VideoTalking videos, re-voiced screen recordings, narrated decks, short films and single clips, made with StartVid, our own presenter model, or Veo, Seedance and Kling.
- Deep LinksFree links that open your app on the right screen, fall back to the web when it isn't installed, and count clicks and opens.
Your first 5,000 emails each month are free.
Send from the dashboard or with one API call. Paced sending, authentication and tracking are included from the first send.
No card needed to start.