Print Labels API

Turn product data into print-ready barcode labels

Send a template and your product data. Get a production-ready PNG immediately, or render a full PDF batch with the same API. The fastest way to design a template is the visual Label Editor — build the layout there, then script it with the API. See Editor access for how sign-in works.

Render your first label Explore API reference

✓ REST and MCP
✓ PNG and PDF output
✓ Data-bound templates

Request JSON

POST https://label-api.gookit.co/api/v1/render

{
  "template": {
    "unit": "mm",
    "width": 50,
    "height": 30,
    "type": "ROLL",
    "elements": [
      {
        "type": "text", "field": "name",
        "x": 3, "y": 3, "width": 44, "height": 7
      },
      {
        "type": "barcode", "field": "barcode",
        "x": 3, "y": 16, "width": 44, "height": 11
      }
    ]
  },
  "data": {
    "name": "Organic Oats",
    "barcode": "GOOKIT-SKU-2048"
  }
}

Output 200 OK

GREEN PANTRY Organic Oats 500g · SKU-2048 GOOKIT-SKU-2048

Format: PNG
Size: 591 × 354 px
Layout: Included

One request, real output

From data to label without rebuilding your print stack

01
Describe the label
Use millimetres or inches and compose text, barcode, QR code, and image elements.
02
Bind your data
Map any element to your own field names, then reuse the template across products.
03
Render and inspect
Receive the PNG plus realized layout details for clipping, font size, and ink bounds.

Quickstart

Render a PNG in under five minutes

You need a Gookit developer key and Python 3 to decode the inline image. The command writes the API response to label.png.

1
Create a developer key
Sign in, open Settings → API Keys, and copy the key when it is shown.
2
Paste the command
Replace the placeholder value, then run the complete block in your terminal.
3
Open label.png
The response also includes realized layout data for programmatic inspection.

Printing on branded stock? Don't hand-type dimensions from a vendor PDF — pull exact geometry for thousands of Avery, Dymo, and Zebra models from GET /api/v1/template-presets, or start from a paper preset in the Label Editor.

Terminal

export GOOKIT_API_KEY="gkdev_your_key_here"

curl --fail-with-body --silent --show-error \
  https://label-api.gookit.co/api/v1/render \
  -H "Authorization: Bearer ${GOOKIT_API_KEY}" \
  -H "Content-Type: application/json" \
  --data '{
    "template": {
      "unit": "mm",
      "width": 50,
      "height": 30,
      "type": "ROLL",
      "elements": [
        {
          "type": "text",
          "x": 3, "y": 3, "width": 44, "height": 7,
          "field": "name", "fontSize": 12, "bold": true
        },
        {
          "type": "text",
          "x": 3, "y": 10, "width": 44, "height": 4,
          "field": "sku", "fontSize": 8
        },
        {
          "type": "barcode",
          "x": 3, "y": 16, "width": 44, "height": 11,
          "field": "barcode", "barcodeType": "code128",
          "showBarcodeText": true
        }
      ]
    },
    "data": {
      "name": "Organic Oats",
      "sku": "SKU-2048",
      "barcode": "GOOKIT-SKU-2048"
    }
  }' | \
python3 -c 'import base64,json,pathlib,sys; image=json.load(sys.stdin)["image"]["dataUri"]; pathlib.Path("label.png").write_bytes(base64.b64decode(image.split(",",1)[1])); print("Saved label.png")'

✓

Saved label.pngThe file is ready to inspect or send to your print workflow.

First PDF

Print a PDF batch without building a template

Starter labels are built-in designs you can print right away. Send a starter ID and one item per product; poll the job for the PDF. Each item's data must include the starter's fields.

Starter	Size	Fields
`product-label-2x1`	2 × 1 in	`name` `price` `sku`	Edit
`inventory-label-4x2`	4 × 2 in	`name` `location` `sku`	Edit
`price-tag-1.5x1`	1.5 × 1 in	`name` `price` `sku`	Edit

Starters print one label per page and sku prints as a Code 128 barcode. They never change once published. To change a design, click Edit to save your own copy in the Label Editor, then send its templateId instead of starter.

Terminal

export GOOKIT_API_KEY="gkdev_your_key_here"

JOB_ID=$(curl --fail-with-body --silent --show-error \
  https://label-api.gookit.co/api/v1/print \
  -H "Authorization: Bearer ${GOOKIT_API_KEY}" \
  -H "Content-Type: application/json" \
  --data '{
    "starter": "product-label-2x1",
    "items": [
      {
        "quantity": 24,
        "data": { "name": "Trail Bottle", "sku": "TB-1042", "price": "$24.00" }
      }
    ]
  }' | \
python3 -c 'import json,sys; print(json.load(sys.stdin)["jobId"])')

for attempt in $(seq 30); do
  JOB=$(curl --fail-with-body --silent --show-error \
    "https://label-api.gookit.co/api/v1/print/${JOB_ID}" \
    -H "Authorization: Bearer ${GOOKIT_API_KEY}")
  case "$JOB" in *'"completed"'*|*'"failed"'*) break ;; esac
  sleep 1
done
echo "$JOB"
case "$JOB" in
  *'"completed"'*|*'"failed"'*) ;;
  *) echo "Job ${JOB_ID} is still rendering. Run the polling loop again." ;;
esac

✓

24 labels in one PDFThe job's url is the PDF. The link is temporary (about 24 hours), so download it to keep it.

Editor access

Two ways to open the Label Editor

Each entry path has its own key family. A gkapp_ key does not authenticate as a gkdev_ key, and vice versa.

01
Shopify merchants
In Shopify admin, open Settings → Open API and select Open API workspace. Launch links are one-use and expire after about 60 seconds. Each launch starts a 24-hour editor session that is not renewed; when it expires, relaunch from Shopify. API keys for this path use the gkapp_ prefix and are created on the same Open API settings page.
02
Web developers
Sign in at /login with email and password, then open /editor directly. API keys for this path use the gkdev_ prefix and are created at Settings → API Keys in the developer portal.

Design it in the browser

Start from your exact label stock, not from numbers

The Label Editor creates templates from the built-in paper catalog — thousands of Avery, Dymo, Zebra, and other models (also available as JSON via the public GET /api/v1/template-presets endpoint). Pick a model, pick one of the designed layouts, and land on a canvas with data-bound elements already previewing sample values — then copy the working API request straight out of the editor.

Grid rows and columns support 1–100 labels each. SHEET spacing comes from the page size, margins, and grid; ROLL2Up derives the page from label sizes and gaps, with zero margins. The catalog retains original source values, including unresolved dimension issues; some presets need paper corrections before the API accepts them. If an older saved template needs repair, open it from the list to correct its paper settings and keep the same template ID. Printing it before repair returns 422.

01
Pick your paper
Search the catalog by brand, model, or size — or deep-link a preset: /editor?preset=AVERY_63.5x38.1_L7160&layout=price-tag.
02
Pick a layout
Twelve designed starting points — price tags, QR, barcode-only, address labels — seeded as data-bound elements, not static text.
03
Copy it as code
Preview the exact PNG the API renders, then export the request as curl or JavaScript. Saved templates are snapshots — later catalog updates never change them.

Built for humans and agents

Give your AI tools the contract, not a screenshot

The OpenAPI document is available as machine-readable JSON. AI agents can also connect through the authenticated MCP endpoint and use the same render service as the REST API.

OpenAPI 3.1Download the JSON contract →/openapi.json Human referenceBrowse every endpoint and schema →/reference/

MCP endpointConnect an authenticated AI agenthttps://label-api.gookit.co/api/v1/mcp

Ready for the full workflow?

Save templates and render complete PDF batches

Move from a single synchronous preview to reusable templates, mail-merge data, and asynchronous print jobs.

Read the API reference