Edit PNG Metadata Online
A Portable Network Graphic (PNG) is a popular image format to share pictures online. PNG often comes with metadata containing information such as creation time, comments, and so on. While these metadata might be useful, you sometimes need to view, edit or remove them for privacy or security reasons. This is where our free online PNG metadata editor comes in.
Before jumping in, we need to understand how PNGs format are structured.
How PNGs are structured
PNG is composed of multiple segments referred to as chunks. Some common chunks that are present within a PNG are:
- IHDR: Contains general information such as width, height, etc.
- PLTE: Contains the color palette of the image
- IDAT: Contains the actual data of the image
- IEND: Contains the end of the image
What is PNG Metadata?
In addition to the chunks above, there are some chunks that are dedicated to store textual data. These chunks are:
- tEXt: Used to store textual data encoded in LATIN-1
- zTXt: Similar to tEXt, but the value is compressed. The standard compression method for this field is zlib
- iTXt: Used to store international textual data. It utilize UTF-8 instead of LATIN-1 character set. Additionally, you can add the translated keyword and the ISO-639-1 code of the language (such as en-uk). Similar to zTXt, this field also supports compression.
These chunks may contain information such as descriptions, software used, etc. If the content of the metadata large, it may bloat your file size and perhaps leak confidential information online.
Do It Privately's Online PNG Metadata Editor: Edit PNG Metadata and Maintain Your Privacy - No Upload Required
We have created a delightful application to let you modify your PNG's metadata in your browser. In contrast to other tools, you don't need to upload your files to our server. Your files will stay in your device.
Using our PNG metadata editor, you can:
- Display metadata that are present within your PNG
- Add new metadata entries such as Author or Comments
- Modify or delete existing metadata entries.
Our tools are supported by most modern browsers.
How does it work?
When you open a PNG using our tool, we parse the PNG and read the tEXt, zTXt, and iTXt chunks that may be present in the file and display it for you. Once you are done modifying or adding entries, we encode the data back into PNG format so that you can save it to your device. Our tools are built using browser's APIs, hence, no file upload required.
What if I Wanted to Delete These Metadata from Multiple Files?
Lucky for you, we got you covered! You can visit our Batch PNG Metadata Remover to remove textual metadata from multiple files with a single click!
Try Our Free Online PNG Metadata Editor Now!
Whether you are someone who values their privacy or a developer who wants to embed some data in their images, you can use our tools right now at no cost!
Reference:
1. W3C. PNG (Portable Network Graphics) Specification (1996). https://www.w3.org/TR/PNG-Chunks.html