PNG Metadata to JSON

About the PNG Metadata to JSON Converter

The PNG Metadata to JSON Converter is a specialized utility designed for developers, digital artists, and AI enthusiasts. While most people view images simply as visual content, PNG files often act as containers for a vast amount of hidden text data. Standard image viewers and operating systems usually ignore this data, but our tool digs deep into the file structure to extract it and present it in a clean, readable JSON format.

Unlike JPEG images, which store metadata in a standard called EXIF, PNG images use a system of "Chunks." These chunks can store anything from copyright notices and software names to massive blocks of text. Recently, this technology has become vital for the AI art community. Tools like Stable Diffusion, Midjourney, and ComfyUI embed the exact generation parameters (the "prompt," seed number, steps, and sampler settings) directly inside the image file using these text chunks. If you have ever downloaded an AI-generated image and wanted to know exactly how it was made, this tool is the answer.

Our tool uses a custom-built engine to read the raw binary data of your image. It identifies and extracts three specific types of text data: tEXt (standard text), zTXt (compressed text, often used for large data), and iTXt (international text with UTF-8 support). It handles the decompression automatically, so you don't need to worry about binary formats. By converting this data into JSON, we make it easy for you to copy, store, or use this metadata in your own applications and scripts.

How to Use the Tool

• Upload Your Image: Drag and drop a PNG file into the upload box, or click to browse your device.
• Automatic Extraction: The tool instantly parses the file. It reads the file header (IHDR) to get technical details like bit depth and color type.
• View Metadata: Any hidden text found in the file is displayed in the JSON output area. You will see the "Keyword" (e.g., "parameters" or "Author") and the "Text" associated with it.
• Export Data: You can copy the JSON directly to your clipboard or download it as a .json file to save the metadata for later analysis.

Frequently Asked Questions

What is the difference between PNG Metadata and EXIF?

EXIF (Exchangeable Image File Format) is the standard used by digital cameras to store data like ISO, shutter speed, and GPS location inside JPEG and TIFF files. PNGs, however, do not natively use EXIF. Instead, they use a flexible system of "Chunks" to store auxiliary data. While some modern software tries to shove EXIF data into PNGs, the native method for storing text in a PNG is via tEXt or zTXt chunks, which this tool reads.

Can this tool read Stable Diffusion prompts?

Yes, this is one of the most popular uses for this tool. Stable Diffusion (and interfaces like Automatic1111) stores the generation prompt, negative prompt, and model hash inside a standard tEXt chunk with the keyword "parameters." Our tool detects this chunk and displays the full prompt text so you can replicate the image.

What is a zTXt chunk and why is it special?

A zTXt chunk contains text that has been compressed to save space. Because it is compressed binary data, you cannot read it by simply opening the image file in a text editor like Notepad. Our tool includes a decompression engine that inflates this data back into readable text before showing it to you.

Is my image data private and secure?

Yes, absolutely. This tool runs entirely in your web browser using client-side JavaScript. When you upload a file, it is processed locally on your own computer's memory. Your images are never uploaded to our servers, ensuring that your photos and their hidden metadata remain completely private.

Why does the output format use JSON?

We output the data in JSON (JavaScript Object Notation) because it is the universal standard for structured data on the web. JSON is easy for humans to read, but it is also incredibly easy for other software to parse. If you are a developer building a gallery or an archive, you can easily ingest the JSON output from this tool into your database.