How can I make my PDF file size smaller without losing quality?

Open your PDF in Acrobat and go to File > Save as Other > Optimized PDF. In the 'Images' section, set color/grayscale images to about 150 dpi and monochrome to 300 dpi. Choose 'JPEG quality Medium/High' (around 85%) for images. In the 'Fonts' section, select 'Subset embedded fonts' and 'Unembed fonts' if not needed. Remove unnecessary objects and user data under 'Discard Objects' and 'Discard User Data'.

What is 'downsampling' in PDF optimization and why does it matter?

Downsampling means reducing the number of pixels in an image within your PDF. It matters because fewer pixels mean a smaller file size, which helps the PDF load faster. You can control how much quality you lose by choosing the right 'dots per inch' (dpi) setting.

If my PDF is a scanned document, how should I optimize it?

If your PDF is a scanned document, you should use the 'Optimize Scanned Pages' option in Acrobat. This tool is designed to work specifically with scanned content, which often has different characteristics than digitally created PDFs. It can help clean up and compress scanned images more effectively, making the file smaller and clearer.

What is the difference between RGB and CMYK colors when optimizing a PDF for screen viewing?

Color Model Best Use File Size Impact. RGB (Red, Green, Blue) For on-screen viewing (websites, emails) Generally smaller file size CMYK (Cyan, Magenta, Yellow, Black) For professional printing Generally larger file size

Why should I unembed fonts when optimizing a PDF?

You should unembed fonts to make your PDF file smaller. When fonts are embedded, the font data is stored inside the PDF. If the viewer already has those fonts on their computer, unembedding them removes this extra data, reducing the file size. However, be careful, as unembedding can sometimes change how the document looks if the viewer doesn't have the correct fonts.

Optimize PDF using Adobe API or SDK in Adobe Acrobat — How-to & AI prompts

AI prompts

3 ways to ask · copy any one

AExecute — “help me do it”Show me how to call the Adobe API to optimize...…+

Show me how to call the Adobe PDF Services API to optimize a PDF file using [my preferred programming language] and [my PDF file].

when the reply comes backWant to see code samples for different programming languages?

BImprove — “do it better”Suggest ways to get the smallest PDF size...…+

Suggest ways to get the smallest possible PDF size using Adobe PDF Services API, while keeping the document readable and clear.

when the reply comes backNeed help with API authentication steps?

CDecide — “help me choose”Help me pick the right optimization settings...…+

Help me pick the best optimization settings in the Adobe PDF Services API for [my use case, like web viewing or printing].

when the reply comes backCurious how to automate PDF optimization for many files?

How to do it

the tool · the steps · what to avoid

1
Sign up for an Adobe Developer account and create a new project in the Adobe Developer Console.
Best practiceRegistering your app ensures you receive the necessary credentials for API authentication.
2
Add the PDF Services API to your project and generate the required credentials (Client ID and Client Secret or Service Account JSON).
3
Install the official Adobe PDF Services SDK for your programming language (such as Node.js, Java, or .NET) using your package manager.
Best practiceRefer to the Adobe PDF Services API documentation for the most up-to-date SDK installation instructions.
4
Import the SDK into your project and initialize the credentials according to the SDK’s guidelines.
5
Configure the advanced PDF optimization options (such as image compression, font subsetting, and object removal) using the SDK’s PDFOptimizeOptions or equivalent class.
Best practiceYou can fine-tune optimization by specifying parameters like image quality, downsampling, and removing embedded thumbnails.
Best practiceBLOGS: For best results, test optimization settings on sample files to avoid excessive quality loss or unexpected file size increases.
6
Call the SDK’s optimize PDF function, passing in your source PDF and the configured optimization options.
7
Save or process the optimized PDF output as required by your application.

In the appWith the API

You can preview the effects of optimization by running the process on a copy of your PDF and comparing file sizes and quality.

The Adobe PDF Services API's /operation/optimizePDF endpoint allows you to programmatically apply advanced optimization settings to PDF files.

Glossary

words on this page

OptimizeTo make something work better for a specific use.ExampleYou optimize your website images to load faster for visitors with slower internet connections.

APIA way for different software to talk to each other automatically.ExampleAn online store uses an API to automatically send shipping details to a delivery service.

EndpointA web address your code sends requests to for a specific job.ExampleThe app sends your payment details to a secure endpoint on the server to process the transaction.

The real tasks

the one, listed here

Replace a large hero image with a compressed version so the page loads faster for users on slow connections.

FAQ

about this task

To optimize a PDF, you send your PDF file to the Adobe PDF Services API's optimize endpoint. The API will process your file and return a smaller, optimized version. You need to set up authentication and use the correct API call in your code.

PDF optimization in the Adobe API means making the PDF file smaller and faster to open by removing unnecessary data, compressing images, and cleaning up the file structure, all done automatically by the service.

Yes, the Adobe PDF Services API lets you choose different optimization levels or settings, such as image quality or which elements to compress, so you can balance file size and document quality for your needs.

Using the Adobe API lets you automate PDF optimization in your apps or workflows, saving time and making sure every file is processed the same way, especially when you have many files or need to do this often.

Adobe's API usually gives more reliable results, better quality, and more options for handling different types of PDFs compared to many open-source tools, but it may require a subscription or API key.

Optimize PDF using Adobe API or SDK

When to use it

AI prompts

How to do it

Glossary

The real tasks

Who does this

FAQ

Sources

Adobe help

Other guides

When it fails