Two types of PDF text
Text-based PDFs
Text-based PDFs are created by software like document editors, spreadsheets, or many accounting tools. The text is embedded as characters. You can select it, copy it, and search it. These files work best with content-based renaming.
Image-based scanned PDFs
Image-based PDFs are created by scanners, phone cameras, or screenshot tools. The page is a flat image. You cannot select individual words, so the tool cannot extract fields from the document content.
Some PDFs are a mix: a scanned image with an OCR text layer added on top. If the text layer is present and reasonably accurate, the tool can often read it.
How to check if your PDF has selectable text
Open the PDF in any viewer and try to select a line of text with your cursor.
- If you can highlight individual words: the PDF is text-based, and content renaming can usually work.
- If the whole page selects as one block or nothing highlights: the PDF is image-based, and the tool will show a "No text found" warning.
- If text selects but looks slightly wrong: the PDF probably has OCR text. It may work, but extracted fields should be reviewed in the preview.
What happens when you drop a scanned PDF into the tool
The tool tries to read text from every file. For scanned PDFs without a text layer:
- The file can still appear in the preview table.
- Extracted fields may show as empty or missing.
- A warning indicates that no text was found.
- You can still give the file a manual name in the preview before downloading.
The tool should not silently skip files or produce names without review. If it cannot read a PDF, it gives you a warning.
How to make scanned PDFs work
If you need to rename scanned PDFs by their content, you need to add a text layer first using OCR, or Optical Character Recognition.
- Desktop PDF software: tools with a "Recognize Text" or "Scan and OCR" feature can add a searchable text layer to scanned pages.
- Batch OCR tools: tools such as OCRmyPDF can process folders of scanned PDFs and add text layers before you use the renamer.
- Scanner software: many scanners and scanning apps can create searchable PDFs at scan time if OCR is enabled.
After OCR, drop the processed files into the renaming tool and review whether the fields are extractable. For invoice scans specifically, see the invoice PDF renamer page for field templates that work after OCR is applied.
A practical workflow for mixed folders
- Drop the folder into the tool: text-based PDFs and scanned PDFs can be checked together.
- Review warnings: the preview table shows which files extracted successfully and which need attention.
- Rename readable files: use your normal naming template for files with selectable text. For example, use the invoice renamer for accounting folders or the rename-by-text workflow for general documents.
- Handle flagged files: enter names manually in the preview, or run them through OCR and process them again.
This lets you handle a mixed folder without sorting every file by type beforehand.
Privacy
Your PDF files and PDF content are not uploaded to our server. Text extraction attempts happen in your browser, even for files that turn out to be image-only.
Limitations
- OCR is not built into the browser tool: the tool reads existing text layers but does not perform OCR itself.
- OCR quality varies: even after OCR, fields may contain errors depending on scan quality, resolution, font, layout, and language.
- Handwritten text: handwriting recognition is beyond standard PDF text extraction and may not produce usable fields.
FAQ
Can this tool OCR my scanned PDFs?
No. The tool reads text that already exists in the PDF. To add a text layer to scanned files, use OCR before using the renamer.
How do I know if my PDF is scanned or text-based?
Open it in any viewer and try to select text. If you can highlight individual words, it is text-based. If nothing selects or the whole page highlights as one block, it is image-based.
Will the tool skip scanned files?
No. Scanned files can still appear in the preview table with a warning. You can name them manually or re-process them after OCR.
Does OCR guarantee perfect extraction?
No. OCR accuracy depends on scan quality, resolution, and font clarity. Low-quality scans or unusual fonts may produce errors. Review extracted fields before downloading.
Is this free to use?
The current browser tool is free to use and does not require signup.
Ready to check your PDFs?
Drop your files into the tool to see which ones have selectable text. Scanned files will be flagged so you know what needs OCR first.
Open the tool