About Compress PDF
Shrink a PDF in four modes: Balanced, Aggressive, Extreme or a target size like 2 MB
Watch: Compress PDF in Action
- How do I compress a PDF to under 1 MB?
- Drop your PDF, choose Target size, type 1 and keep the unit on MB, then compress. The steps run gentlest first and stop as soon as the file fits. If it cannot get that small, you get the smallest version it reached, with its final size and a note.
- Will compressing blur my text?
- In Balanced, no: text stays real, selectable text and only the pictures inside are reduced. Aggressive, Extreme and Target size can turn pages into pictures when they have to go further, and text on those pages is then drawn as part of the picture, so it is not selectable. Each level is marked in the list, so you can download a gentler one.
- Why did compressing barely change my file size?
- The bytes in a PDF are mostly in its pictures. If your PDF is mostly text, or is a scan that is already compressed (JBIG2 or JPEG 2000), Balanced has little to shrink without changing how it looks, and the tool tells you so. Aggressive then turns pages into pictures level by level, and Extreme goes on to grey and black-and-white pages; every level is a downloadable file and text on converted pages is no longer selectable. If it has photos, try Balanced first.
- ¿Comprimir un PDF hará que el texto no se pueda seleccionar ni buscar?
- En Equilibrado, no: solo ordena el archivo y reduce las imágenes que contiene, por lo que el texto sigue siendo texto real y seleccionable, y se conservan los vínculos, los marcadores y los campos de formulario. Agresivo y Extremo, y Tamaño objetivo cuando tiene que llegar tan lejos, convierten las páginas en imágenes, así que el texto de esas páginas ya no se puede seleccionar; cada nivel aparece en la lista con su tamaño y marcado, y puedes descargar un nivel anterior en su lugar.
- Can compressing make my file bigger?
- Not any more: if a result isn't noticeably smaller than your original, the tool says so and keeps your original instead of offering the larger file. A file that is already under your Target size is left alone.
- What's the difference between Balanced, Aggressive, Extreme and Target size?
- Balanced tidies the file and shrinks the pictures inside, first to about 140 dots per inch and then picture by picture, so text stays selectable (the last level can soften fine detail in photos). Aggressive does that and then turns pages into pictures in finer and finer steps. Extreme goes further and makes every page grey, then pure black and white. Target size lets you set an exact limit, like "under 2 MB", works through the levels gentlest first and stops as soon as the file fits, aiming a little under the limit so it passes size checks.
- ¿Mis archivos se suben a un servidor para comprimirlos?
- No. La compresión, incluido el cambio de tamaño de las imágenes, se hace por completo en tu navegador. Tu PDF nunca sale de tu dispositivo.
- Will a scanned or image-heavy PDF compress differently than a text document?
- Yes. A scan is one big picture per page, so it has the most room to shrink. A short, mostly-text PDF has the least, and is the case where the tool will tell you there is nothing worth shrinking.
How to use Compress PDF
Drop a PDF into the upload area, then choose how far to go. Balanced tidies the file's structure, empties blank pages and shrinks the pictures inside, first to about 140 dots per inch and then picture by picture; text stays selectable, though the last level can soften fine detail in photos and links, bookmarks and form fields are kept. Aggressive does all of that, then turns pages into pictures in finer and finer steps (empty areas dropped, flat areas stored as fills, photos, text and small print at lower resolutions); text on those pages is no longer selectable. Extreme goes on from there: every page becomes grey at 70 dots per inch, then pure black and white, and colour is lost. Target size lets you set a limit such as "under 2 MB": the steps run gentlest first, stop as soon as the file fits, and if it can't fit you are told the final size and why.
Every finished level is a complete file in one list, each with its own Download and Compare buttons, so you choose the one that looks right. You see the original and the result side by side, page by page, before downloading. If a mode can't make the file noticeably smaller, the tool says so and keeps your original. As soon as the file loads, a short breakdown shows how much of it is pictures, embedded fonts and page content, with a one-line hint on which mode is likely to help.
When to use it
The clearest use case is a PDF that's too large to email or upload: a scanned multi-page document, a PDF exported from a design tool with high-resolution images, or a merged file assembled from several image-heavy sources. Target size is the one to use when a portal or an email provider has a specific limit, because it stops at the gentlest level that fits.
When not to use it
If your PDF is mostly text (a contract, an invoice, a report without photos), its words and layout already take very little room, so tidying the structure saves little. If it is a scan stored in scanner formats (JBIG2 or JPEG 2000), it is already compressed for scans, and only Extreme (black and white, with a lossless and a smallest version) usually shrinks it. Aggressive and Extreme show the size after each level: blank pages emptied, pages as pictures with empty areas dropped, finer pieces, softer pictures, softer text, then grey and black and white. You can download any level. Pages that are already small stay real text; pages turned into pictures are no longer selectable or searchable, and the level list marks them. If you need the highest fidelity for professional printing, skip compression.
Tips for best results
Start with Balanced and look at the comparison before trying Aggressive. For a size limit, use Target size rather than guessing: it stops at the gentlest level that fits and tells you why if nothing does. If you will send a file repeatedly (a template, a recurring report), compress the master copy once and keep that as your working file.
Limitations
Every mode re-saves pictures at lower quality, and that can't be undone inside the output file (your original is untouched on your device). Scans lose a little sharpness as the saving grows. Some unusual picture types, such as masks and CMYK images, are left as they are by Balanced. Aggressive and Extreme turn pages into pictures: that keeps the page size, but text then can't be selected or searched, and links, bookmarks and form fields on those pages are lost. Extreme also drops colour, and its smallest black-and-white version stores look-alike letters once and reuses them, so very rarely a letter can be swapped; read important numbers in the original. Several files at once: the Several files switch compresses up to 5 PDFs on the trial (more on a paid plan) with the same setting and counts as one use. A file that cannot be made smaller comes back unchanged.
Privacy
Compression runs entirely in your browser: the pictures are decoded, resized and re-saved locally using your browser's own image tools, and the file never leaves your device. Speed therefore depends on your own device, so a large file may take longer on an older phone or laptop.
How to compress a PDF to 1 MB
1. Drop your PDF. 2. Choose Target size, type 1 and keep the unit on MB. For 200 KB, type 200 and switch the unit to KB. 3. Press Compress. The steps run gentlest first and stop as soon as the file fits. 4. Compare the result with your original page by page, then download it. If it cannot get that small, you get the smallest version it reached, with its final size and a note that the target was not met.
Which mode should I use?
Start with Balanced and look at the comparison. Go further only if the file is still too big.
| Mode | What it changes | Text afterwards |
|---|---|---|
| Balanced | Tidies the file's structure, empties blank pages and shrinks the pictures inside (about 140 dots per inch first, then picture by picture) | Stays selectable; links, bookmarks and form fields are kept |
| Aggressive | Everything Balanced does, then turns pages into pictures in finer and finer steps | Not selectable on pages turned into pictures; their links, bookmarks and form fields are lost |
| Extreme | Everything Aggressive does, then every page becomes grey at 70 dots per inch, then pure black and white | Not selectable on pages turned into pictures; colour is lost |
| Target size | Runs the levels gentlest first and stops as soon as your limit is met | Depends on how far it had to go; each level is marked in the list |
Compressing scanned PDFs
A scan is one large picture per page, so it has the most room to shrink. Balanced shrinks those pictures first. If that is not enough, Aggressive and Extreme work on the whole page, and Extreme's black-and-white versions are usually the smallest for text scans. Scans already stored in scanner formats (JBIG2 or JPEG 2000) are compressed for scans, and usually only Extreme makes them smaller. Pages turned into pictures can no longer be searched or selected, so keep your original if you need that.
Is my PDF uploaded?
No. The pictures are decoded, resized and saved inside your browser, and the file never leaves your device.
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