Easily Compress PDF Files Online

Try an easy-to-use online solution for reducing the size of your PDF and forget about complications.

Drag & Drop the File Here

Choose File

How it works

Upload a PDF

Compress any scanned or image-based PDF in seconds. Drag and drop your document into the box or import it from an online location.

Compress Your Document

Wait for the upload to finish. Click the ‘Compress Now!’ button to process your file immediately or the Trash button to start over.

Use it for Free

Forget about paid and downloadable applications! AltoCompressPDF is totally free and allows you to have an unlimited number of uploads.

Encrypted File Processing

With our app you are always in control of your data safety. Each document you upload is processed via an encrypted connection.

Compatible with Any Device

AltoComressPDF is a web-based app. Run it on any of your devices regardless of its type. It works with desktop, mobile, or OS.

Compress Documents in the Cloud

Processing files in the cloud enables you to operate faster. Compress PDFs on any Internet-connected device and forget about complications.

Characteristics

File extension	.pdf
Internet media type	application/pdf
Description:	PDF is the Portable Document Format developed by Adobe Systems. It was invented to streamline the process of sharing and viewing files independent of any software, OS or hardware. Individuals can use PDFs wherever and whenever they want on any device. PDF files can contain textual and visual data as well as links, buttons and more. PDFs can be also password protected and edited with special programs.
Technical Details:	Graphics are represented in PDF very similarly to that of PostScript. PDF graphics use a device-independent Cartesian coordinate system which describes the surface of a page. The page description uses a matrix to scale, rotate, or skew graphical elements. The graphics state is a collection of graphical parameters that may be changed, saved, and restored by a page description.
Developed by	ISO
Initial Release:	15 June 1993
Useful links:	https://acrobat.adobe.com/us/en/acrobat/about-adobe-pdf.html https://fileinfo.com/extension/pdf

Customer Questions and Answers

Question:

Can I somehow reduce the size of my PDF file without affecting its readability?

Answer:

Sure! Choose an online platform. AltoPDF service provides you with the AltoCompress feature. All you need is to upload a file, click the Compress Now button and download the reduced PDF document to your device. The service is available for free and runs on all internet connected devices.

By Keith on June 01, 2018

Question:

How can I compress a 3GB file to less than 100MB on my PC?

Answer:

You can use an online service that runs on any internet connected device. Go to AltoCompress and reduce the size of your PDF file in jUST a few clicks. All you have to do is to upload a document to the server, click the Compress Now button and save the newly created file. You may also choose the Work on your PDF option to continue editing your PDF.

By William on May 30, 2018

Question:

I want to find an online program that can compress my image from 300kb to 150kb. BTW, the image is saved in PDF format. Waiting for some advice.

Answer:

There are not many programs that provide such services. Most of them are expensive or require you to install a software to your device. However, some online platforms can still help you. Go to AltoCompress and reduce the size of any PDF file with a few clicks. Click the Choose file button, upload a document, click on Compress Now and download the newly created file to your device. You may also continue working on your document.

By Jared on May 26, 2018

See All Question

Customer Reviews

Olivia

06/02/2019

AltoCompress is a great tool when it comes to reducing the size of your PDFs. I use it all the time. The whole procedure takes a few simple steps. OH, and you can also edit your PDF online.

Grayson

01/02/2019

I’m almost out of free storage space on my smartphone, that’s why I think AltoComress is very helpful. Now I can reduce PDFs and store them on my phone or save them to Google Drive in one click.

See All Reviews

Rate the AltoCompressPDF

4.5

7,320Votes

How-to guide

How to reduce the size of a PDF document online

In order to compress a PDF, open AltoCompressPDF.com in your web browser.
Click Choose File to add a document from your hard drive.
Click a cloud storage service icon to add a PDF stored online.
Wait for your upload to finish, then click Compress Now!
Click the Trash icon in case you’ve uploaded the wrong document.
Wait while your new PDF is being generated, then choose what you want to do with it.
Click Work on your PDF to redact it or share it with other users.
Click Download Now to download the resulting PDF back to your device.

How To Compress a PDF File?

How to reduce the file size of a PDF?

To clear up more storage space, simply make your files more compact. One way to do this is by compressing files. By “packaging” a file, you make it take up less disk space. If you’re constantly adding, removing and organizing documentation stored on your computer, this may be an optimal solution for you. You are also provided with the ability to take many documents and compress them into one file, which it should be smaller than the combined size of the originals. Since PDF is one of the most popular formats for documents, you may easily find tools for transferring your PDFs.

PDFs enable users to store significantly more data. Users can then compress PDF online to 100kb. What is more, a user can post files on a web page for someone else to download and send big documents as email attachments, as most email services limit the size of each email message. It is well known, that documents may become corrupted when they are transferred over the internet in a less compressed format. Attaching documents one-by-one takes more time and effort than a bulk send. Instead just compress multiple PDFs into one and then attach them to your email message. All in all, it is easy for you to personally open reduced files from web pages or from your email application.

How to Reduce the Size of Your PDF Without Compromising Image Quality

Choose online service that offers PDF optimizer tools which exist on the cloud, so you have access to variety of operations wherever you are and whenever you need them. Even if the storage of your tablet or smartphone is minimal, AltoCompressPDF still operates. Just upload your PDF and make one click to compress PDF file size. You don’t need to download and install any additional software. No payments are required. Compress pdf files absolutely for free. See, how easy it to how to reduce PDF file size without losing quality:

Click the Choose button and select a document to compress into PDF or use simple drag and drop functions to put your chosen document into the box above.
Click Compress and see how the compression will be performed in seconds. Delete your files and upload a new one before reducing its file size.
Download the final result or start over again.
After the procedure is finished, you have the possibility to edit or sign your document electronically. Easily resize PDF image if needed.
Send the compressed PDF via email or fax.

Note that you are provided with encrypted file compression, so you may be sure that all your information is safe. All data is deleted from the server right after the compression is finished and can’t be accessed by any unauthorized party.

Another advantage is compatibility with all major operating systems. Compress PDF on Mac, Windows or Linux. Compress for pdf even on-the-go with your mobile device. Rather than wasting your time and efforts, use a solution, that smartly atomizes your document management for free. Try it now.

Did you know?

PDF documents can be compressed

To compress Word or Excel documents down to a more manageable size, just convert them to PDF. This way, you won’t lose any quality characteristics. Another benefit is the editing option. You can edit a PDF document as well as enhance it with visual and graphical elements.