Email Rendering API

Render emails on real devices. From code.

One REST call uploads your HTML and returns light and dark mode screenshots from real Outlook on Windows, Gmail on real phones, and Apple Mail — not headless-browser simulations. Your pipeline renders, your team reviews.

# Upload your email and trigger real-device renders
curl -X POST https://emailqa.live/api/v1/projects \
  -H "Authorization: Bearer eq_your_api_key" \
  -d '{"name": "Spring campaign", "html": "<!DOCTYPE html>..."}'

curl -X POST https://emailqa.live/api/v1/projects/{slug}/renders \
  -H "Authorization: Bearer eq_your_api_key" \
  -d '{"clients": ["outlook-desktop", "gmail-ios"]}'

# -> 202 { "id": "rj_...", "status": "queued" }
# Poll for screenshots, or let the render.completed webhook tell you.

What teams build with it

CI/CD pipelines

Render every template change automatically. Push a commit, get real-device screenshots, catch the Outlook bug before it ships — no human clicking required.

Campaigns at scale

Agencies and teams producing dozens of campaigns a month script the upload-render-review loop: one API call per campaign instead of one afternoon.

Embed in your product

Building an email tool? Pipe your users' emails through the API and show them real client screenshots and preview links inside your own app.

Automated QA gates

Block a send until renders complete and a human approves. Webhooks notify your system the moment results land, and approvals live in the review UI.

Real hardware, not headless Chrome

Your email is delivered over SMTP and opened in the actual client apps — including the Word-engine Outlook on Windows that causes most rendering bugs, and Gmail on physical iPhones and Android devices.

Desktop

  • Outlook Windows (Classic, Word engine)
  • Outlook Mac (New)
  • Outlook Web
  • Apple Mail (Mac)
  • Gmail Web (Mac & Windows)

Mobile — real phones

  • Gmail (iOS)
  • Gmail (Android)
  • Apple Mail (iOS)
  • Outlook (iOS)
  • Outlook (Android)

Light and dark mode screenshots for most clients, automatically. See the live client catalog

Machines render. Humans review.

Every API render lands in the same shareable review UI the rest of EmailQA uses: your pipeline renders overnight, your team or your clients open the preview link in the morning, drop pin comments, and approve. No other rendering API ends in a collaboration tool.

1

Push

Your CI uploads the HTML and triggers renders with one API call.

2

Render

Real devices open the email and screenshot it in light and dark mode.

3

Review

Webhook fires, reviewers get the preview link, feedback and approval happen in the UI.

Frequently asked questions

What is an email rendering API?

An email rendering API lets your software request email client screenshots programmatically instead of clicking through a web UI. You POST your email HTML, the service opens it in real email clients (Gmail, Outlook, Apple Mail), and you get back screenshots showing exactly how subscribers will see it. Teams wire it into CI pipelines so every template change is rendered and reviewed automatically before send.

How is EmailQA's API different from a website screenshot API?

Generic screenshot APIs load your HTML in a headless Chrome browser — which is not how email clients render. Outlook on Windows uses Microsoft Word's rendering engine, Gmail strips styles and rewrites CSS, and mobile clients apply their own dark-mode transformations. EmailQA sends your email through real SMTP delivery and screenshots it inside the actual client apps on real hardware, including real iPhones and Android phones. What you get back is what subscribers genuinely see.

Is this a Litmus API alternative?

Yes. Litmus sells API access as a custom-priced add-on on top of plans that start around $500/month — teams report API costs in the thousands per year. EmailQA includes full REST API access on the Business plan at $99/month with 1,000 render previews included. The API docs are public at emailqa.live/docs/api, so you can evaluate the endpoints before paying anything.

Is this an Email on Acid / Mailgun Inspect API alternative?

Yes. Mailgun Inspect (Email on Acid's successor) includes API access from ~$99/month with 1,000 previews — EmailQA matches that price and allowance. The difference is what surrounds the API: EmailQA renders land in a collaborative review UI with pin comments, guest review links, and approval workflows, so your pipeline renders and your team (or your clients) review without a separate tool.

Which email clients can I render through the API?

Eleven real clients: Outlook on Windows (the classic Word-engine version that causes most rendering bugs), Outlook on Mac, Outlook Web, Apple Mail on Mac and iPhone, Gmail Web on Mac and Windows, and Gmail plus Outlook on real Android and iOS devices. Most clients return separate light and dark mode screenshots automatically. The live catalog is available unauthenticated at GET /api/v1/clients.

How do I get results — polling or webhooks?

Both. Poll GET /api/v1/renders/{id} for job status with per-client progress, or subscribe to the render.completed webhook and get notified the moment results are ready. Webhook payloads are HMAC-signed. Results stream in progressively, so fast clients appear while slower mobile devices finish.

How fast are API renders?

Single desktop clients complete in about a minute; a full 11-client fleet render takes 10–15 minutes because real mobile devices are the slowest lane. Re-submitting identical HTML returns cached screenshots in about a second. Most CI setups render one or two critical clients (like Outlook on Windows) per commit and save full-fleet runs for release candidates.

What does the API cost?

API access is included in the EmailQA Business plan at $99/month: everything in Pro (unlimited UI rendering, collaboration, approvals) plus the REST API with 1,000 render previews per month. One preview equals one client screenshot. Failed renders don't count against your quota. Need more volume? Contact us.

Start with the docs — they’re public

Evaluate every endpoint before creating an account. API access is included in the Business plan.