Developer API

Personalized images,
generated on demand.

Send a JSON payload. Get back a finished, personalized image. Drop it into any email, app, or workflow - instantly, at any scale.

Read the docs Get your API key

Start with 500 free images · No credit card needed

REQUEST · POST /v1/images

{
  "design_id": "AbOHw7ix50q",
  "format": "jpg",
  "layers": [{
    "layer_id": "name",
    "text": "Lisa"
  }],
  "background": {
    "image_url": "Sydney.jpg"
  }
}

200 OK · image/jpeg

How it works

From design to live image in three steps

No complex setup. No SDK required. Just a simple REST API you can call from any language or tool.

Design your template

Use the visual editor to create an image template. Add text, image, and shape layers for the merge tags you need.

Call the API

POST your recipient's data - name, company, photo URL, any custom field. One call per image.

Use the image anywhere

Get back the image file itself. Attach it to an email, ad, chat message, or certificate - wherever you need it.

API capabilities

Everything you need to build with

A clean, well-documented API designed to handle real production workloads.

Rendered on demand

Each call renders your design with the values you send and returns the image in the same response - no queue, no polling.

Multiple merge tags per image

Combine name, company, location, photo, and any custom field in a single image. Stack as many layers as your design needs.

Dynamic backgrounds

Pass a different background image URL per request. OKZest composites it into your template on the fly - no extra design work.

Fallback values

Set a default for any layer. If a merge tag is missing or empty, your image still looks perfect - no broken placeholders.

Bulk generation

Loop through your contact list and generate thousands of unique images in a single script.

Team API keys

Create separate API keys per workspace or team member. Revoke access instantly without affecting your other integrations.

Quick start

A few lines to your first personalized image

cURL Node.js Python PHP

generate-image.sh

# Generate a personalized image for Lisa

curl -X POST https://api.okzest.com/v1/images \
  -H "x-api-key: YOUR_API_KEY" \
  -H "Content-Type: application/json" \
  --output image.jpg \
  -d '{
  "design_id": "AbOHw7ix50q",
  "format": "jpg",
  "layers": [
    { "layer_id": "name", "text": "Lisa" },
    { "layer_id": "company", "text": "Acme Corp" }
  ],
  "background": {
    "image_url": "https://example.com/office.jpg"
  }
}'

# Response: the image itself (a JPEG here, because the body sets "format": "jpg"), saved to image.jpg
# "format" can be "jpg", "png", "webp" or "pdf"

Full API reference

Every endpoint, parameter, and response code documented. Try requests directly from the docs - no Postman needed.

API key in your dashboard

Find your key under Settings → API. Create team keys with limited scope, or rotate them any time.

Test with the free plan

Every account starts with 500 free images - no credit card needed. Good enough to build a full proof of concept.

Read the full documentation

docs.okzest.com/api/introduction

Get started

Your first API call
takes about 5 minutes.

Create a free account, grab your API key, and start generating personalized images before your next coffee break.

Start for free Read the API docs

Personalized images,generated on demand.