Quickstart
Generate your first image in under a minute. MostlyRender turns a template (a canvas with named layers) into a PNG, JPEG, WebP, or PDF — over a simple REST API.
# 1. Get an API key
Create a key in the app under Settings → API keys. Keys look like
mr_live_… (production) or mr_test_… (testing). Send it as a Bearer token on every
request. See Authentication.
# 2. Create a template
In the editor, design a template and give your layers names — a text layer named
title, an image layer named photo, and so on. The layer name is the API
parameter you fill at render time. See Templates as parameters.
# 3. Render it
curl https://api.mostlyrender.com/v1/renders \
-H "Authorization: Bearer mr_live_…" \
-H "Content-Type: application/json" \
-d '{
"template": "tpl_abc",
"modifications": { "title": "Renders that never go dark" },
"output": "png"
}'
{
"id": "rnd_abc123",
"url": "https://img.mostlyrender.com/mostlyrender/renders/rnd_abc123.png",
"output": "png"
}
The url is a public, CDN-cached asset — drop it straight into an <img>, an email,
or an OG tag.
# 4. Or use an SDK
from mostlyrender import MostlyRender
mr = MostlyRender("mr_live_…")
out = mr.render("tpl_abc", modifications={"title": "Renders that never go dark"})
print(out["url"])
# Next steps
- Renders — every option for
POST /v1/renders. - Batch — many images in one call.
- Screenshots — capture any URL.
- Signed render URLs — render-on-the-fly for
<img>/OG tags. - The full API reference.