One request.
Sent through your Gmail.
Call MailGo from your website or app’s backend. Your connected Gmail is always the sender.
Get connected
Connect Gmail, then open your account to copy your API key. If someone invited you, they can handle the integration after you authorize Gmail. Open your account
Send an email
curl https://mailgo.w1.nz/v1/send \
-H 'Authorization: Bearer YOUR_API_KEY' \
-H 'Content-Type: application/json' \
-d '{"to":"recipient@example.com","subject":"New enquiry","text":"A new message from your website.","replyTo":"visitor@example.com"}'| Field | Requirement |
|---|---|
to | Required. One recipient email. |
subject | Required. Up to 200 characters; no line breaks. |
text / html | At least one required, up to 50,000 characters each. Provide both for plain-text and HTML alternatives. |
replyTo | Optional reply address. |
No custom sender, cc/bcc, attachments, or bulk recipients. Maximum request size: 128 KiB.
Handle the response
{"ok":true,"status":"accepted"}Accepted means Gmail accepted your request, not that the email reached the inbox. Find sent copies in Gmail. MailGo keeps no email content, message IDs, sending history, or counters.
| Response | What to do |
|---|---|
400 / 413 / 415 | Check the JSON fields, content type, and request size. |
401 invalid_api_key | Check your API key or copy it again from your account. |
403 account_inactive | Resume sending or connect Gmail in your account. |
409 gmail_reconnect_required | Reconnect Gmail in your account, or request a fresh invitation. |
429 gmail_limit_reached | Gmail has reached a limit. Wait before trying again. |
422 gmail_rejected | Gmail rejected the message. Check the recipient and account. |
502 delivery_uncertain | Check Gmail Sent before retrying. The email may already have been sent. |
503 | The service is temporarily unavailable. Try again later. |
Keep the key on your backend
Web pages and mobile apps should call your own backend, which calls MailGo with the key. Do not ship the key in client-side code. Your product handles form validation, bot protection, and duplicate submissions.
MailGo has no queue, automatic retries, or request deduplication. Each Gmail account remains subject to Google’s own sending limits.