Migration from SendGrid

Move transactional sends from SendGrid to SuperSend TX — receipts, password resets, alerts, and invites still go out over POST /emails with a simpler JSON body than SendGrid's v3 mail send payload.

Why teams switch

Straightforward HTTP API — one POST /emails instead of nested personalizations / content arrays
Owned transactional mail infrastructure, separate from cold/outbound reputation
Sandbox → Pool → Dedicated — test for free, run production on a shared transactional network, isolate on managed servers when you need allowlists

Quick mapping

SendGrid	SuperSend TX
`SG.` API key	`stx_…` API key (`Authorization: Bearer`)
`https://api.sendgrid.com/v3/mail/send`	`https://api.supersendtx.com/emails`
`personalizations[].to[]`	`to` (string or array)
`from.email` + `from.name`	`from` (single address string)
`content[]` with `type` / `value`	`html` and/or `text`
Dynamic templates (`template_id`)	Template `alias` on send
Event Webhook	Webhooks + dashboard activity
ASM / unsubscribe groups	Managed unsubscribe + suppressions

Minimal send

SendGrid (v3):

curl -X POST https://api.sendgrid.com/v3/mail/send \
  -H "Authorization: Bearer $SENDGRID_API_KEY" \
  -H "Content-Type: application/json" \
  -d '{
    "personalizations": [{ "to": [{ "email": "[email protected]" }] }],
    "from": { "email": "[email protected]" },
    "subject": "Hello",
    "content": [{ "type": "text/html", "value": "<p>It works.</p>" }]
  }'

SuperSend TX:

curl -X POST https://api.supersendtx.com/emails \
  -H "Authorization: Bearer $SUPERSENDTX_API_KEY" \
  -H "Content-Type: application/json" \
  -d '{
    "from": "[email protected]",
    "to": "[email protected]",
    "subject": "Hello",
    "html": "<p>It works.</p>"
  }'

Node.js

SendGrid:

import sgMail from '@sendgrid/mail'
sgMail.setApiKey(process.env.SENDGRID_API_KEY!)
await sgMail.send({
  to: '[email protected]',
  from: '[email protected]',
  subject: 'Hello',
  html: '<p>It works.</p>',
})

SuperSend TX:

import { SuperSendTX } from 'supersendtx'

const client = new SuperSendTX(process.env.SUPERSENDTX_API_KEY!)
await client.emails.send({
  from: '[email protected]',
  to: '[email protected]',
  subject: 'Hello',
  html: '<p>It works.</p>',
})

Webhooks

SendGrid Event Webhook posts JSON arrays of events. SuperSend TX sends one signed JSON object per delivery with SuperSendTX-Signature (HMAC-SHA256). Map event names as follows:

SendGrid event	SuperSend TX
`processed`	`email.sent`
`delivered`	`email.delivered`
`deferred`	`email.delivery_delayed`
`bounce`	`email.bounced`
`dropped`	`email.failed` or `email.suppressed`
`open`	`email.opened`
`click`	`email.clicked`
`spamreport`	`email.complained`

Use Send test event on the dashboard webhooks page (or POST /emails/test) to verify your handler before cutover.

Checklist

Create a SuperSend TX API key (stx_…)
Add and verify your sending domain (SPF, DKIM, return-path)
Swap the client to api.supersendtx.com and map fields per table above
Recreate webhook endpoints and update signature verification
Send from Sandbox, then production after domain verify

Compare

Marketing overview: SendGrid alternative.