How To

How to Merge PDF Files Without Losing Quality: Tips and Tricks

How to Merge PDF Files Without Losing Quality

Merging PDFs into one document can help businesses that deal with lots of different files, like proposals and contracts. This is important since bad document handling can lead to losing more than 21% of work productivity — you could lose a lot of money just trying to find the right documents. But, when you merge PDF files into one, work gets easier, teams work better together, and the business looks more professional.

Lumin has a functionality that fixes this problem. It combines PDFs clearly and without losing any quality. If you want to learn how to merge PDF files, this article will give you tips on how to get started. Let’s dive in.

Selecting the Right Tool

Combining multiple PDFs into a cohesive document is now more common, but achieving this without sacrificing quality could pose a challenge. Now, the key to preserving quality is in choosing the right software. Here are some available options:

  • Free Online Tools: PDF merge online free tools are convenient and readily available. However, you have to choose carefully since some have limitations. You may experience quality loss due to compression techniques used to reduce file size for online processing. You may also have security concerns when uploading confidential documents to third-party platforms.
  • Desktop Software Solutions: Dedicated desktop software offers greater control and security when handling sensitive documents. However, these programs often come with a price tag and require installation and configuration, adding an extra step to your workflow.

Preparing PDF Files for Merging

After choosing the right tool (ideally a robust PDF editor like Lumin!), prepare your files for a seamless, quality-preserving merge PDF process. Here is a little pre-merge housekeeping to ensure a smooth and successful result.

Organizing Files for Efficient Merging

Here are some steps to organizing your files:

  • Eliminate Redundancies

Before combining, scan your files for any duplicate pages or content that could bloat the final document and create confusion. Also, remove unnecessary pages to ensure a clear and concise combined document.

  • File Naming Consistency

Rename your PDFs to indicate their proposed order in the combined document. For example, a pdf fill online with titles like “Proposal_Part1,” “Proposal_Part2,” and so on will suffice. This simplifies the process and reduces the risk of accidentally misplacing sections within the final document.

  • Organize by Content

If your PDFs contain specific sections, consider combining them consistently based on content. So, you can combine a quarterly report that includes separate PDFs for sales figures, marketing data, or financial summaries and create a comprehensive report with a clear content flow.

Checking for Compatibility and Potential Issues

This is another step in your preparation that ensures top-quality final documents:

  • Font Compatibility

Ensure all PDFs have compatible fonts. When there are font inconsistencies, you could get garbled text or missing characters in the combined document. If you are unsure about the compatibility of your fonts, consider using common fonts like Arial or Times New Roman across every fillable PDF.

  • Password Protection

If any of the source PDFs are password-protected, ensure you have the passwords readily available before initiating the merge. Trying to remove passwords during the process can cause errors.

  • Scanned Documents

To combine scanned documents, ensure they are high-resolution scans. Low-resolution scans will appear blurry or pixelated in the final merged document.

Step-by-Step Guide to Merging PDF Files

Let’s see the step-by-step process of combining your PDFs while preserving quality and streamlining your workflow.

Step 1: Installing and setting up the merging tool

For a dedicated PDF merging software, you would have to follow the installation instructions the vendor provides. This typically involves downloading the software, running the installer, and following any on-screen prompts for configuration.

However, with Lumin, you don’t need separate software for merging – it’s built right in! So, you’ll only be incorporating code snippets into your existing application to leverage Lumin’s power.

Step 2: Selecting PDF Files for Merging

Most desktop software provides an interface for you to browse and select the PDF files you want to combine. Ensure you select them in the desired order for the final document.

On the flip side, Lumin’s PDF editor allows you to specify the location and order of your PDF files directly within your application’s code. This means you can integrate the merging process seamlessly into your existing workflows. In essence, you will have a system where proposals are automatically compiled from various sections stored in separate PDFs.

Step 3: Executing the merging process

Desktop software typically offers a simple “Merge” button once you’ve selected your files and configured settings. Clicking this button initiates the process.

With Lumin, after specifying the files and compression settings, initiate the merge function. The tool handles the entire process efficiently and securely within your application. This eliminates the need for separate software or manual file transfers, minimizing the risk of errors and streamlining your workflow.

Step 4: Reviewing the merged PDF and checking for quality loss

While Lumin’s technology ensures a high-quality merge, it’s always good practice to review the final document after you merge two PDF files.

  • Zoom in on images and graphics within the merged document. Look for any pixelation, blurring, or changes in color that might indicate a quality issue.
  • Check text formatting to ensure all text remains clear and legible. Check for font inconsistencies or missing characters that could have occurred during the merge.

With Lumin, you can be confident that your merged documents maintain the professional quality you expect. However, taking a few minutes for a quick review provides an extra layer of assurance.

Tips for Preserving Quality During PDF Merging

While Lumin excels at maintaining quality during merges, there are additional strategies you can employ to ensure your merged PDFs retain their professionalism:

Avoiding Unnecessary Compression

Lumin’s high-quality lossy compression offers a good result, but it’s best reserved for less critical documents. However, for documents like contracts, presentations, or reports with crucial visual elements, prioritize lossless compression to avoid any degradation.

Using High-Resolution Source Files

The quality of your merged document can only be as good as the quality of the individual PDFs you’re combining. Ensure all source files are high-resolution scans or PDFs created with clear and crisp visuals. Avoid combining low-resolution documents, as they will contribute to a blurry or pixelated final product.

Ensuring Consistent Settings Across Merged Documents

Inconsistent fonts can lead to text garbling or missing characters in the final merged document. Ensure all source PDFs use compatible fonts. Alternatively, Lumin offers font embedding options within the PDF editor to maintain consistency as you merge PDF files online.

For documents with specific color requirements, ensure all source PDFs use the same color profile to prevent color shifts in the merged document.


Merging PDFs efficiently without sacrificing quality is the goal for streamlined workflows. So, ensure that you choose the right tool, like Lumin, to prepare your files and source high-resolution documents. Also, understand the compression options and settings for the perfect balance between file size and quality to merge PDF online flawlessly and promote team collaboration and efficiency.