Getting the balance right: how to compress a PDF without sacrificing its quality For Free

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Getting the balance right: how to compress a PDF without sacrificing its quality

An image is worth a thousand words. What if this image is a part of a PDF file? Well, then it might be worth thousands of kilobytes as well.

PDFs have won our hearts as the best file format for viewing, printing, and sharing documents. However, when it comes to editing them, it’s like riding the hassle bus.

If you’re having a hard time changing your PDF’s size to make it more web-friendly or to be able to save some storage space, worry not, you’re in the right place to learn how to do just that.

Read our guide below. It will help you downsize PDF documents in seconds.

PDF in a nutshell

Portable Document Format (a.k.a. PDF) is a digital file format that allows you to easily send, open, and read documents across different platforms. It was created by Adobe back in the early '90s and now is one of the most used formats in the world. According to the PDF Association, as of 2016 alone , there were over 2 billion PDFs on the internet, and 73 million new files in this format were saved every day in Google Drive and Mail. It’s no wonder that we run into them virtually every day.

PDF format seems to be like a Jack of all trades when it comes to reading and viewing a whole range of documents, from the forms we submit to the IRS to online catalogs and e-books. One of the most significant advantages of PDF is that it preserves a document’s original layout, making it perfect for printing and on-screen reading.

It’s interesting to mention that PDF was initially designed as a medium for exclusively sending and viewing information to prevent recipients from changing or modifying it. However, as more and more PDF readers and editors appear on the market, the format started gaining significant improvements. It’s become more flexible and now gives users more power in terms of editing and collaborating on documents.

With all the offline and online tools available to us, just about anyone can work with PDFs with no special skills or training. Before we get to the tools that make editing and compressing PDFs a bit easier, we will cover some basic information about the PDF format.

Pros and Cons of the PDF format

PROS:

High quality

PDF is excellent for exporting and combining images, texts, and a whole range of fonts and optimizing them for printing, sharing, and editing.

Readability

PDF preserves original design, graphics, fonts, and ensures that your content will be shown the way it should on different devices.

Delivery

Another advantage of PDF over Word is that it lets you send read-only documents preventing third parties from messing with your originals.

Legal admissibility

PDF is a read-only file that, when altered, leaves an electronic trail, making it suitable for court admission.

Interactivity

The PDF format allows you to add music, videos, graphics, and even hyperlinks.

Convertibility

It doesn't’t matter in which format your document initially started in: Word, Excel, or PowerPoint. You can easily convert it to PDF and vice versa. Modern tools let you process conversion in less than a minute.

Despite the growing popularity of PDFs in today’s world, they have a few significant disadvantages. The main Achilles heel of this format is the inability to edit the file as we can do in Microsoft Word or Google Docs. Because of this, users often run the risk of content responsiveness on mobile platforms, pix elation, and size compression issues.

CONS:

Responsiveness

The recent research by Campaign Monitor shows that 60% accounts for all emails opened on mobile devices. PDFs are not always mobile-friendly. You need to continually swipe and pinch to zoom in and read the text.

Edibility

PDFs are hard to edit because, as we mentioned earlier, they were designed for online distribution. You can edit PDF with some paid or free editors, but they do not offer a full suite of editing capabilities like, for example, MS Word does.

Size

Upon converting from other formats, editing, or creating files from scratch, PDFs often end up being too large to upload, send, or submit, even if they are only a few pages long. That is fine for printing but can make it difficult to change words later or block out a section of text.

When the size of a PDF file matters

Storage limit

If you are dealing with an enormous amount of PDF documents that you cannot remove and need to keep for your records, you might sometimes come to the point when you have to go over your system’s storage limit for file size. This is when reducing the size of a PDF will be of great help.

Email attachment requirements

Most email services don’t accept files larger than 20-25 MB. You can turn to online cloud storage solutions, such as Dropbox, to send a large PDF. However, if you do not want to share your data through a cloud service, you might need to make a PDF file smaller. Take a look at some major email services and their limits.

Online document submission

Most social or legal institutions accept files no larger than 10 MB. For instance, if you want to upload your resume to Glassdoor, you need to shrink the PDF file size to 5 MB.

Web distribution

On average, users spend less than 15 seconds on a website unless its content is highly engaging. The speed of the website has always been a major ranking factor for Google. If you post e-books, how-to guides, and other PDF content as a part of your marketing strategy, you need to add files that are not too large to download. Otherwise, it might harm your users’ experience and thus, your Google ranking.

What influences the size of a PDF?

Before shedding some light on issues related to PDF sizes, let’s take a look at a PDF’s basic anatomy. The typical PDF includes the following elements:

Content stream (text)

Embedded fonts

Vector graphics

Raster graphics

Hyperlinks

Bookmarks

Attachments

Metadata

Comments

Points to consider before compressing a file

Splitting a file into multiple smaller files does not always help in reducing the output. The reason for that lies behind the anatomy of PDFs. If the original document uses embedded fonts, each of the output files should also contain them even after the split. Embedded fonts ensure the PDF file displays the original layout across all devices. However, at times, they can account for more than 30% of the PDF size.

PDFs can not be infinitely scaled without loss of quality. If you compress a 300 MB file down to 50 MB, it might not be adequately compressed. To get around this limit, you would probably need to re-scan the document and then re-compress it.

Compression depends on what is inside the PDF document. For example, suppose you have high-quality images that take 90% of the space. In that case, re-compressing the photos using a lossy compressor might get you space-saving at the cost of image quality.

Lossless vs lossy compression

Roughly speaking, when you compress a document, you launch specific algorithms to shave it of unnecessary redundancies in order to change its size. These algorithms scan the document for areas that are not very noticeable to the human eye and can be shrunk.

Generally, there are two major PDF compression types: lossless and lossy.

With lossy compression, you permanently remove that data from the document that the algorithms view as non-noticeable. The keyword here is “permanently.” That is why you need to make sure there is a backup copy of your document saved if this size reduction technique removes more than you needed it to. To understand how it works, let’s imagine you have a PDF, the largest part of which is composed of visuals. Lossy compression will help you save an impressive amount of storage space, but the document’s quality will be greatly affected.

Alternatively, lossless compression reduces the file size and leaves the quality of the visuals intact. This type makes PDFs more efficient size-wise by removing some unnecessary content, such as hyperlinks or bookmarks, and restructuring the way the data is written. As you can imagine, it can’t compete with lossy compression if you need to shrink the document’s size considerably. In most cases, the maximum size you can reach with this compression type isn't’t smaller than ½ of the original document. However, the lossless technique is used when the original data in a document needs to keep up with the archiving standard and the important original data should remain unchanged.

PDF compression and compliance with standards

When it comes to changing PDF size, you might find yourself on the horns of a dilemma facing a choice between size or quality. However, your choice of file compression type should entirely come down to specific use cases.

For instance, in heavily regulated industries like medical or legal ones, it’s imperative to comply with the document archiving standards (PDF/A). One of them is the ability to preserve the documents in their original state and the option to roll back any changes made to the document. Medical staff and legal authorities are required to store documents in PDF/A format to be able to reproduce the originals in the future.

As you have probably guessed, you will not be able to keep up with the PDF/A standard if you compress industry-critical documents with lossy compression.

Measure twice, cut once: how to optimize the PDF file

Compressing a document in Portable Document Format is a real trade-off between quality and size. However, there is an excellent way to strike a perfect balance between them.

As you probably understood, if you have a huge PDF (regardless of the number of pages it has), the odds are that it contains high-quality images that take up much of the space. At the same time, you may also run into issues when your multi-page PDF file is entirely composed of text, but its size goes over the limit. In both cases, your attempts to decrease the size of PDF might be useless.

If you want to defeat your enemy, you must know your enemy. For that, you need to understand exactly what your file is made of. Start by checking the proportion (in percentage and bytes) of each element in the document. You can do so by running a Space Usage Audit.

Steps to audit your file’s usage space with Adobe Acrobat Pro:

Open up a file in the Adobe Acrobat Pro desktop application.

Select File in the top left corner.

Click Save as Other and pick Optimized PDF… from the menu bar.

In the top right, choose the option Audit space usage….

A dialog box will open showing you how much space is taken by each PDF element.

How to make your PDF upload-friendly

Avoid scanning

It often happens that people get the idea of combining PDFs wrong. They print electronic files and then scan them as one PDF file. The file ends up being too big. Unless the files are initially in paper form, you don’t need to scan them. Instead, you can combine them using online tools like pdfFiller.

Resize and optimize images for PDF

There is an array of tools for changing an image’s size without losing quality. One of the best ways to do it is to use Adobe Photoshop, and change dimensions and DPI/PPI numbers.

Use grayscale or monochrome bitmap images

Color images take much more space than monochrome or grayscale ones do. If you don’t need to retain color information in your document, converting color images to grayscale or monochrome will be your best bet.

Export document elements in vector formats

Vectors, as opposed to bitmap (raster) images, weigh much less. For example, if you export some graphs or charts from Excel, make sure to save them in a vector graphic format.

Use PDF standard fonts

A PDF format comes with 14 standard fonts such as Times-Roman, Helvetica, Courier, etc. You should use them to save a considerable amount of space for storage.

Remove embedded fonts

No matter what fonts you have installed on your computer, PDF will always display the original layout and fonts. It is possible because PDF comes with embedded fonts. If you remove them, your PDF reader will do everything possible to replace them with the ones you have on your computer. This way, you can significantly reduce a file’s size, but be mindful that there might be a striking difference between the original and output layout.

Flatten transparency

Transparency flattening glues layers of a file together. It helps make elements more compressed. In addition to that, transparency flattening is required by most printing shops.

Remove outside attachments

If you have documents attached to your PDF that can be sent or viewed independently, you might want to remove them. In addition to that, when you compress your PDF document, external files remain intact. So there is no reason for keeping them in your document unless required by the receiving party.

Set up the right exporting options

If you export a file made in Adobe Illustrator, uncheck the Preserve Editing Capabilities option. It can compress it too much. If you’relooking for an excellent quality vs. size proportion, it’s not your best bet.

How can you optimize a document in Adobe Pro?

Armed with the detailed report by Space Usage Audit, you may decide for yourself what part of your PDF should be compressed or changed.

Open up a PDF in the Adobe Acrobat Pro desktop application.

Select File in the top left corner.

Click Save as Other and pick Optimized PDF… from the menu bar.

A dialog box will open and display the options for optimizing the document.

7 quick ways to compress PDF: online vs. on desktop vs. on mobile

If you don’t want to be bogged down with file optimization technicalities, here are seven ways you can change the size of a file quickly.

1. How to change a file’s size with Adobe Acrobat Reader DC

Open a file in Acrobat DC.

Click File and then Compress PDF. For some users, it might be shown as Reduce File Size, depending on which testing category the users fall into.

Click Save and choose the location to save the compressed document.

Adobe has also recently introduced new free online tools for working with PDFs. You don’t need to download software to your computer. However, a PDF compressor will only be available to you if you upgrade your free plan. This applies to the desktop version as well. In addition to that, for many users that only occasionally need to convert documents, Adobe’s prices are out of reach.

2. How to resize a file in Preview for Mac

Preview for Mac is a life-saver when it comes to working with PDF. It lets you compress a file in a few simple steps.

Right-click the file you would like to compress.

Select Open With, and choose Preview in the menu bar.

Pick File in the top toolbar, and then click Export.

Click the Quartz Filter menu, then select Reduce File Size.

Hit the Save button.

One of the most significant advantages of Preview is that it works offline. What is more important, it’s super simple to use and is free of charge. This tool is well-suited for users who do not care about quality reduction. With Preview for Mac, you cannot control the compression level.

3. How to reduce a PDF file size with PDF Squeezer

If you would like to have a more extended suite of tools, you might want to check PDF Squeezer. With this software, you are more in control of exactly what you change in your document.

Open the file in the app or launch the app and drag and drop the file into the app.

Click the drop-down menu, set the preferred DPI.

Click Save or Save As to download files under a different name.

PDF Squeezer can compress any file by up to 90×. It allows batch-compressing and password protection.

4. How to downsize a PDF with Smallpox

Smallpox is a self-explanatory online platform that features a versatile suite of PDF tools, including file compression.

Upload your file to the Smallpox website.

Choose between two levels of compression: Basic or Strong.

Hit Compress.

Download the compressed file.

One of the main challenges of compressing PDF is to anticipate the extent to which the document will be downsized. Smallpox shows you in advance how much you can squeeze it. Note, you can perform up to two tasks per day. If you go over this limit or prefer Strong conversion, you can sign up for a 7-day free trial and commit to a subscription.

5. How to make a PDF smaller with Soda PDF

Soda is another reliable tool for working with PDF files. You can upload a PDF directly from your browser.

Upload a document to the platform.

Choose one of three compression options depending on the quality you want to get.

Click Compress.

Soda also lets you preview the compressed file before downloading it. You don’t need to register or create an account to run compression. Besides, there is no limitation as to how many PDFs you can compress for free.

6. How to reduce a PDF file’s size with pdfFiller

pdfFiller is a robust platform that offers a wide range of features at a very competitive price. Some of them are genuinely uncommon for most PDF editors, such as data and payment collection forms, document password protection, access to an online library of forms for any use case.

Add the extension to your Google Chrome.

Choose a file from your computer or pull it directly from your Google Drive.

Click Compress Now.

After you get a compressed file optimized with good PDF quality, you can continue editing the file. If you work with PDFs regularly, pdfFiller is your best bet. With the whole arsenal of tools that it offers, you can securely store, edit, sign, password-protect, automate, and streamline all your PDFs from a single platform.

You might also go ahead and split the document into multiple documents so that each file will be smaller.

What other PDF-related tasks can you can solve with pdfFiller?:

Edit and annotate PDFs on desktop or mobile

Create PDFs from scratch

Create and share interactive fillable PDF forms

Manage e-signature workflows: e-sign, e-notarize, and submit tax forms online

Pull data directly into PDFs.

Connect your document to the apps, Arms, and ERPs you work in

Collaborate on PDFs with your colleagues in real time

Distribute documents in a safe and secure manner

7. Change a PDF’s size on your phone with loved

The name of the app speaks for itself. loved provides an extensive list of features that allow it to perform almost any PDF-related task. PDF compression is among the free features.

Launch the app and add a document.

Open the document and click the wrench icon.

Choose Compress PDF and select one of three compression options.

Hit Compress.

The application is available in the App Store and Google Play.

Alternative ways to preserve a PDF file’s quality and make it upload-ready

You might consider other options to get around size limits if you have highly sensitive information or are not ready to sacrifice a byte of the document quality and need a pixel-perfect PDF file.

Saving the file in a different format

Even though it might sound obvious, many people stick to PDF format because it’s the best format for high-quality print. Though, that mostly applies to image-heavy documents such as wallpapers, portfolios, and brochures. If this is your case, you can try and save it in TIFF format, it offers LAW compression (one of the lossless compression types).

Sending PDFs to a zip folder

If you have some large documents on your computer that you seldom open but are not ready to remove for good, it’s better to save them in a ZIP archive. In this way, you will declutter and tidy up your computer space. Moreover, you can password-protect the archive so that no one can access it. In addition to that, ZIP makes it easy to get around the size limit for emailing PDFs.

Uploading files to a cloud storage

With the cloud storage platforms such as One Drive, Google Drive, or Dropbox, you can send PDFs of any size in a few clicks. If you use a specific email service, you’re likely to use the storage platform associated with this service like Google Drive for Gmail. Alternatively, you can use online tools like WeTransfer. It lets you easily send large documents via email or shareable link for free. With the Pro plan, you can even send up to 20 GB at once, add branding, and set a password.

Splitting the document

You can also split the document into multiple independent copies so that each one will be smaller and let you upload or send the file in parts. However, sometimes, you may end up having disproportionately large files. In this case, you need to go through the Audit Storage Space again and remove any embedded fonts if possible.

Using third-party services for mobile optimization

There is not much more we can do to reduce the PDF size online and improve the mobile responsiveness of the PDF. However, some online tools, such as Issue, can turn your PDF into a mobile-friendly interactive book or Instagram story.

Converting to Word and back

You can use any online converter, including pdfFiller, to convert your PDF into DOC or DOCX format and back. You can also downsize the file as you create and save the Word document and convert it to PDF. All you need is to select Minimum size (publishing online) in the export settings.

Final thoughts

Whether you’re an undergraduate student sending your very first resume in PDF or you’re a sales representative putting together proposals in the range of 100 or more pages, you might run the risk of facing file size limits. Whatever your case is, you need a reliable tool to work with PDF files. There are plenty of them out there, but they don’t offer a one-size-fits-all solution.

There is no rule of thumb that will help you apply the right settings to reach the needed balance between quality, resolution, and size. What you need is to experiment with different options when looking for the optimal size.

One of the most popular file size converters is Adobe. However, you might find yourself overspending on the tools that you don’t even use. If you need a simple compression feature, you might check out the services we listed above.

We know the pain of working with PDF format. That is why we suggest using pdfFiller. It’s effortless to use and comes with a great feature set. The best part about it, it lets you create, edit, sign, redact, and keep your PDFs in order without spending a fortune.

pdfFiller complies with major industry standards and makes working with PDFs 100% secure. You can take pdfFiller for a risk-free test drive and take more control of your documents. Once subscribed, you can switch between plans to decide which one suits you the best. You have 30 full days to explore all features.

pdfFiller is trusted by millions of users. It’s easy to use and effortless to implement into your daily document management routine.

So go ahead and try out pdfFiller today!

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