Initializing Secure Environment…
Initializing Secure Environment…
Drop in a PDF and see where its size comes from, byte for byte: images, fonts, page content, vector graphics, colour profiles, attachments, metadata and the document structure. It lists the heaviest pages, the largest images with their pixel size and format, and the fonts embedded in full. Then it says in plain words what would make the file smaller. The file is read in your browser and never uploaded.
A PDF is usually big because of images: scanned pages and photos stored at high resolution make up most of the size of most large PDFs. Fully embedded fonts, the same image stored several times, attached files, and earlier saved versions kept inside the file are the other common causes. This analyzer measures each of these in your file and says which one to fix.
A screen shows about 100 to 150 pixels per inch and a printer needs about 300. Phone cameras and many scanners capture far more, and PDF creators often embed the image exactly as captured. An A4 page photographed at 12 megapixels holds four times the pixels a 300 DPI print needs. The analyzer shows the pixel size of each image so you can see this directly, and compression brings each image down to a sensible resolution.
Fonts embedded in full instead of only the letters used can add hundreds of kilobytes each, especially for Asian scripts. A logo pasted onto every page can be stored once per page. Spreadsheets or other PDFs can be attached invisibly. Editors that save incrementally keep every earlier version inside the file, which also means text you deleted may still be recoverable; the Redaction Checker can show what those earlier versions contain.
Every object in the file is classified by what it is and what refers to it: images by their type, fonts by the font descriptors that point at them, page content by the pages that use it. Sizes are the bytes as stored in the file, so the categories add up to the size your file manager shows. Page weights count only the images a page actually draws, not every image listed in shared resources.
In most large PDFs, images are the cause: scanned pages, phone photos or pictures stored at a much higher resolution than a screen or printer needs. A 300 DPI colour scan is about 1–3MB per page. Other causes are fonts embedded in full, the same image stored more than once, attached files, and earlier versions of the document saved inside it. The analyzer shows which of these applies to your file.
A few pages with full-resolution photos or scans can easily be 10MB or more. A single photo from a modern phone is 12 megapixels. Open the file in the analyzer and look at the largest images list: if one image is several MB, that is the answer.
Many editors save changes by appending them to the end of the file, so the original stays inside too. The analyzer reports how many saved versions the file contains. Rewriting the file, for example by compressing it, keeps only the latest version.
For images, which is the usual case, use Compress PDF and set a target size such as 1MB or 500KB. It re-encodes the images and keeps text sharp. For attachments, flatten or re-export without them. For duplicate images and full fonts, compression also fixes those.
No. The analysis runs in your browser and the file never leaves your device. It is not changed either; the analyzer only reads.
Everything that is not the content itself: the dictionaries that describe each page and object, the cross-reference table that lets a reader jump to them, and any data from earlier saved versions. In a typical file it is a few percent.
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