By ZoeTue. 12 May. 20264min Read

Free Online PDF to Black and White Converters: What Works (and What Doesn't)

Compare free online tools that convert PDFs to black and white while preserving text searchability. Plus: when to use a desktop app instead.
Free Online PDF to Black and White Converters: What Works (and What Doesn't)
Quick Answer

Free online services that convert PDFs to black and white include ILovePDF (Grayscale PDF tool), PDF2Go, and PDF24—all three preserve the text layer, so documents remain searchable after conversion. For most personal documents, these tools work reliably. However, free online converters require uploading your file to a third-party server, which is unsuitable for confidential business documents. Enterprise teams handling sensitive content typically use a desktop PDF application that processes files locally.

You have a color PDF—a report, a form, a contract—and you need it in black and white.

Maybe the printer only does monochrome. Maybe you want a smaller file size. Maybe the archive standard requires grayscale.

Free online converters seem like the obvious answer. But not all of them work the same way, and a surprisingly common concern goes unspoken:

Does the converted PDF still let me search the text?

This guide tests the most reliable free online options, explains exactly what happens to searchability, and flags when a desktop tool is the better call.

 

What "Black and White" Actually Means for a PDF

Before comparing tools, it helps to understand that a PDF is not a single image. It contains:

  • visual layer — colors, images, backgrounds
  • text layer — selectable, searchable characters
  • Sometimes an OCR layer — extracted text from scanned documents

When you "convert to black and white," a good converter changes the visual layer only. The text and OCR layers stay intact. A poorly implemented converter rasterizes the whole page into an image, destroying the text layer entirely.

Always check: after conversion, can you select text with your cursor? If yes, searchability is preserved.

 

Top Free Online PDF to Black and White Converters

1. ILovePDF — Grayscale PDF

ilovepdf.com/grayscale-pdf

ILovePDF's dedicated grayscale tool is one of the most widely used free options. It converts color images to grayscale, preserves the text layer, and typically outputs a smaller file.

Text searchability preserved  Yes
File size limit 200 MB
Page selection  Whole file only
Requires account No
Processing Cloud (EU servers)
Output format PDF
Speed Fast (under 30 seconds for most files)
Best for: Personal documents, quick one-off conversions, files under 200 MB.

2. PDF2Go — Grayscale Conversion

pdf2go.com

PDF2Go offers a "Grayscale" option under its PDF editing tools. Files can be uploaded directly or pulled from Dropbox, Google Drive, or URL. Output preserves the text layer.

Text searchability preserved  Yes
File size limit 50 MB (free); larger with account
Page selection  Whole file only
Requires account No
Processing Cloud
Output format PDF
Speed Moderate
Best for: Users who need to import from cloud storage and want a clean, no-signup interface.

3. PDF24 — Color to Grayscale

tools.pdf24.org

PDF24 is notable for two reasons: it has no file size limit in its online version, and it also offers a free offline desktop app (PDF24 Creator) for Windows.

Text searchability preserved  Yes
File size limit None (online)
Page selection  Whole file only
Requires account No
Processing Cloud (Germany)
Output format PDF
Offline option  PDF24 Creator (Windows)
Best for: Large files that exceed ILovePDF or PDF2Go's free limits; users who want a companion offline tool.

4. Adobe Acrobat Online

acrobat.adobe.com

Adobe's online version offers limited tools without a subscription. Color-to-grayscale conversion is not available as a standalone online tool—it requires Adobe Acrobat Pro (desktop).

B&W / Grayscale conversion (online)  Not available
B&W / Grayscale conversion (desktop Pro)  Via Preflight or Output Preview
Requires subscription Yes (Acrobat Pro, ~$23.99/month)
Note: If you already have Acrobat Pro, use it—it gives the highest-quality grayscale output. But for free online conversion, it is not an option.

Head-to-Head Comparison

Tool Free Searchability File Limit No Account Needed Offline Option
ILovePDF 200 MB
PDF2Go 50 MB
PDF24 None ✅ (Windows)
Adobe Acrobat online

The Searchability Question: What the Tools Actually Do

All three recommended tools (ILovePDF, PDF2Go, PDF24) preserve text searchability because they process PDFs at the color profile level—they change how colors are rendered without rasterizing the text layer.

HOW TO VERIFY AFTER CONVERSION
  1. Open the converted PDF in any viewer
  2. Press Ctrl + F (Windows) or Command + F (Mac)
  3. Search for a word you know is in the document
  4. If the search finds it, the text layer is intact 
If search returns no results, the conversion tool rasterized the document (converted it to images). This is a known issue with some lower-quality tools. Avoid converters that output image-only PDFs.
 

When Free Online Tools Are Not the Right Choice

Free online converters are convenient for personal use. But for enterprise workflows, they create problems that are easy to underestimate:

1
Data security

Every file you upload to a free online tool leaves your network. Even tools with GDPR-compliant privacy policies temporarily store your file on a third-party server. For contracts, HR records, financial reports, or any document covered by compliance requirements (HIPAA, GDPR, ISO 27001), uploading to a third-party server is a policy violation.

2
No control at scale

If 50 employees each use a different online tool, you have no visibility or consistency. Files may be processed on servers in unknown jurisdictions.

3
No audit trail

Enterprise document workflows typically require logging who accessed, modified, or printed a document. Free online tools provide no audit trail.

The enterprise alternative: LynxPDF processes files entirely on the user's device—no upload, no third-party server. IT teams can deploy it across the organization via GPO, SCCM, or Microsoft Intune, and configure black-and-white print settings as the default for all users. Documents stay within the corporate network.
For step-by-step instructions using LynxPDF on Windows and Mac, see How to Make a PDF Black and White
 

Which Online Tool Should You Use?

Your Situation Recommendation
Non-sensitive document, one-off conversion ILovePDF (simplest interface)
File over 200 MB PDF24 (no size limit)
Need to import from Google Drive or Dropbox PDF2Go
Enterprise team, sensitive documents LynxPDF (desktop, processes locally)
Highest print quality needed Adobe Acrobat Pro (desktop)

 

Frequently Asked Questions

Q: Are there free online services that reliably convert PDFs to black and white and preserve text searchability?

A: Yes. ILovePDF, PDF2Go, and PDF24 all preserve the text layer during grayscale conversion. After converting, open the PDF and use Ctrl+F (Windows) or Command+F (Mac) to confirm text search still works.

Q: Do free online PDF converters store my files?

A: Most reputable services delete uploaded files automatically after processing (typically within 1–24 hours). ILovePDF and PDF2Go both state files are deleted after download. However, the file is still transmitted and temporarily stored on a third-party server—this is a risk for sensitive documents.

Q: Is there a free way to convert PDFs to black and white without uploading?

A: Yes. PDF24 Creator is a free Windows desktop app that performs the conversion locally. LynxPDF offers a 14-day free trial and also processes files locally without upload.

Q: Will converting a PDF to grayscale reduce its file size?

A: Usually yes. Color image data is larger than grayscale. For image-heavy PDFs, file size can drop by 30–60%. For text-only PDFs, the reduction is minimal.

Summary

For free online PDF-to-black-and-white conversion:

  • ILovePDF is the easiest option for most users
  • PDF24 handles large files and has a free offline app for Windows
  • All three top tools preserve text searchability

For enterprise use:

    • Avoid uploading confidential files to online tools
    • LynxPDF processes locally, supports IT deployment at scale, and delivers consistent results across Windows and Mac

Get Started with LynxPDF Today!