Does this upload my response anywhere?

No. Detection, decoding and rendering all happen in your browser, so labels and shipment data stay on your device.

What does it recognise?

ZPL labels, PDF files and PNG, JPEG, GIF and WebP images. Other Base64 values (such as 2D barcode data) are counted but not shown.

Can I paste something that is not valid JSON?

Yes. A single Base64 value, a data: URI, a copied fragment such as "encodedLabel": "...", or text with Base64 inside all work.

Base64 Auto Preview

Runs locally

Paste an API response (or just a Base64 string) and this tool finds every Base64 value in it, works out whether it is a ZPL label, a PDF or an image, and shows a preview you can download. No need to dig out the field or pick the right converter first.

Paste a Base64 value, or a JSON response that contains one

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Your data is processed locally in your browser and is not uploaded.

Learn more about this tool⌄

How it works

If the input is JSON, every string value is checked; otherwise the whole paste, or any long Base64 run inside the text, is checked. Each value is decoded locally and identified by its content: a PDF starts with %PDF-, an image with its PNG, JPEG, GIF or WebP signature, and a ZPL label is text containing ^XA ... ^XZ. ZPL is rendered with the same renderer as the ZPL Viewer. Nothing is uploaded to a server.

Common use cases

Previewing the encodedLabel returned by a carrier API such as FedEx without decoding it by hand
Checking which documents (label, invoice, waybill) a shipping API response actually contains
Pulling a PDF or image out of a JSON payload found in logs or a database

Frequently asked questions

Does this upload my response anywhere?: No. Detection, decoding and rendering all happen in your browser, so labels and shipment data stay on your device.
What does it recognise?: ZPL labels, PDF files and PNG, JPEG, GIF and WebP images. Other Base64 values (such as 2D barcode data) are counted but not shown.
Can I paste something that is not valid JSON?: Yes. A single Base64 value, a data: URI, a copied fragment such as "encodedLabel": "...", or text with Base64 inside all work.