Quick answer
What is Compare PDF files used for?
Purpose
What does Compare PDF files do?
Expect a text-oriented comparison, not proof that every visual element is unchanged.
Who normally uses it?
This guide is useful for people searching, comparing, recognizing, completing, or inspecting document information. The working tool is focused on one outcome: What changed between two drafts, in words not pixels.
Prepare
Before you start
- Determine whether the document has a text layer or is an image-only scan.
- Keep the original available while checking extracted text, differences, fields, or metadata.
- Treat uncertain recognition and layout results as items to verify rather than final facts.
Worked example
Find wording changes between two contract drafts.
This example describes a practice task, not a document you need to upload to us. Use your own authorised file and keep the original.
- 01
Prepare the example
Choose the older and newer text-based PDFs in the correct order.
- 02
Make the change
Run comparison and review each reported text change alongside both originals.
- 03
Check the result
Expect a text-oriented comparison, not proof that every visual element is unchanged.
When the result is not right
Troubleshooting Compare PDF files
If changes appear missing, test text selection and OCR image-only drafts where needed. Review layout, images and signatures visually as a separate check.
Before you rely on the output
A changed picture or layout can be important even when extracted wording is identical. Scans may have no usable text layer.
Open the saved result as well as the preview. Keep the original until you have checked the pages and information that matter for your task.
Better results
Practical tips for Compare PDF files
Use OCR first when text search or extraction cannot see words that are visible on the page.
Review warnings and confidence notes before relying on extracted or compared information.
Check names, dates, totals, identifiers, and form answers against the page itself.
Honest expectations
Limitations and important checks
The result depends on the structure and quality of the source document, so visually inspect the exported file before relying on it.
Browser memory varies by device. Very large or unusually complex PDFs may work better when processed in smaller groups.
Questions and answers
Compare PDF files FAQ
Direct answers to the questions people commonly ask before using this tool.
What is Compare PDF files used for?
Compare PDF files is a browser-based Filozy tool built for this task: What changed between two drafts, in words not pixels. It runs on this device, creates a separate result, and does not require an account or document upload.
Can I use Compare PDF files on a phone or tablet?
Yes. Compare PDF files works in a current mobile browser. Complex PDFs can need more memory, so keep the tab open, avoid switching apps during processing, and inspect the result before closing the page.
Does Compare PDF files upload my file?
No. The selected file is opened and processed by code running in this browser tab. Document bytes and filenames are not sent to Filozy.
Will this change my original file?
No. Browsers cannot silently overwrite the file you selected. Filozy creates a separate result for you to save or pass to another local tool.
What should I check after using Compare PDF files?
Check the visible preview and the result summary. The comparison works on document text rather than pixel differences, making wording changes easier to review. Keep the original until the new output has been opened and verified.
Do I need an account or subscription?
No account is required for this browser-side tool. It runs on the device and does not use a document-upload allowance or daily server quota.
Privacy
Where does my document go?
For this tool, the document stays in the browser tab. Filozy can load same-origin support files such as its PDF engine, fonts, or OCR data, but the selected document bytes and filename are not sent with those requests.