How to Scan a Document to PDF (Phone or Scanner)

Converting a physical document into a PDF is one of the most common tasks in any office or home — receipts, contracts, IDs, forms, handwritten notes. This guide covers every method: phone camera, flatbed scanner, scanner app, and how to make the resulting PDF searchable with OCR.

Method 1: Scan with Your Phone (Fastest)

Your phone camera is the fastest scanner you have. Both iPhone and Android have built-in scanning tools that produce clean, cropped PDFs.

iPhone (Notes App)

1. Open the Notes app
2. Create a new note or open an existing one
3. Tap the camera icon → Scan Documents
4. Position your document — the camera auto-detects edges and captures automatically
5. Scan additional pages if needed, then tap Save
6. Tap the scan thumbnail, then the Share icon
7. Choose Save to Files → select iCloud Drive or local storage
8. The file saves as a PDF

You can also use the Files app (tap the three-dot menu → Scan) on iOS 16+ for a direct save.

Android (Google Drive)

1. Open the Google Drive app
2. Tap the + button → Scan
3. Point the camera at your document
4. The camera auto-captures when it detects the document (or tap the shutter manually)
5. Adjust corners by dragging the blue handles
6. Tap Done → Give the file a name → Save

The resulting PDF goes directly to your Google Drive. Download it from Drive for use elsewhere.

Samsung (built-in)

Samsung Galaxy phones include a built-in scanner in the Camera app. Open the camera, tap the scan icon or use the document scanning mode in Extra Photo Settings. Output saves as PDF to the gallery.

Method 2: Scan with a Flatbed Scanner (Best Quality)

For professional-quality scans — contracts, photographs, documents with small print — a flatbed scanner outperforms a phone camera.

Optimal settings:

• Resolution: 300 DPI for standard text; 600 DPI for small print or fine details
• Color mode: Grayscale for text documents; Color only if color matters
• File format: PDF (most modern scanners output PDF directly) or TIFF (then convert)
• Page size: Match to document (A4, Letter, Legal)

Windows — Scanner App

1. Connect your scanner via USB or network
2. Open Windows Scan (free from Microsoft Store) or use your scanner's native software
3. Choose PDF as the output format
4. Set 300 DPI, Grayscale
5. Place document on the glass, align to the corner marker
6. Click Scan → choose save location

macOS — Image Capture

1. Connect your scanner
2. Open Image Capture (in /Applications or search Spotlight)
3. Select your scanner in the left sidebar
4. In Scan To: choose a folder; Format: PDF; Resolution: 300 DPI
5. Click Scan

For multi-page documents on macOS, use Preview: File → Import from Scanner → select the scanner → scan all pages → File → Export as PDF.

Method 3: Scan with a Dedicated App

Scanner apps use your phone camera and apply automatic edge detection, perspective correction, and contrast enhancement — significantly improving on raw camera shots.

Adobe Scan and Microsoft Lens are the most capable free options. Both apply automatic enhancements, allow multi-page scanning in a single session, and export to PDF.

Method 4: Use a Multifunction Printer/Copier

Most office printers (HP, Canon, Brother, Epson) with a scanner function can save directly to PDF:

1. Place document in the document feeder (ADF) or on the flatbed glass
2. Press Scan on the printer panel
3. Choose Scan to Computer, Scan to Email, or Scan to USB
4. Select PDF as the format
5. Retrieve the file from your chosen destination

For multi-page documents, use the ADF (Automatic Document Feeder) — it scans all pages without manual feeding. ADF quality is slightly lower than flatbed for fragile or thick documents.

Make Your Scanned PDF Searchable

When you scan a document, the PDF contains an image — not real text. This means:

• You cannot search for words with Ctrl+F
• You cannot copy-paste text from it
• Screen readers cannot read it (inaccessible)
• You cannot fill in form fields

OCR (Optical Character Recognition) adds a text layer to your scanned PDF, solving all of these issues.

How to add OCR:

1. Go to PDFlexa OCR
2. Upload your scanned PDF
3. Select the document language
4. Click Run OCR — process runs in your browser
5. Download the searchable PDF

After OCR, the document looks identical but Ctrl+F works, text is copyable, and accessibility tools can read it. Read the full guide on using OCR →

Tips for Better Scans

Lighting matters most for phone scans. Use natural light from a window — avoid shadows across the document. Overhead artificial light creates hot spots. Don't use a flash directly on the document.

Keep the camera parallel to the page. Angling the camera creates perspective distortion (text gets smaller on one side). Hold it directly above the document.

Flatten the document. Wrinkled paper creates shadows and distorts OCR accuracy. Press down gently on the edges when scanning.

Scan darker for faded documents. If the original ink is faded, increase the scanner contrast setting or adjust in your scanning app to darken the output.

300 DPI is enough for text. Higher DPI (600 DPI) creates much larger files with no visible benefit for standard office text. Reserve 600 DPI for photographs or very small print.

Name files immediately. A scan named doc_2026_06_29_001.pdf is much easier to find later than scan_0034.pdf.

Combine Multiple Scans into One PDF

After scanning several pages separately, use Merge PDF to combine them into one document:

1. Go to PDFlexa Merge PDF
2. Upload all your scan files
3. Drag to reorder pages
4. Click Merge PDF
5. Download the combined document

Scan to PDF vs Scan to TIFF/JPG

For documents, PDF is almost always the right choice. It preserves layout for multi-page documents and works with every operating system, email, and document system.

Frequently Asked Questions

How do I scan multiple pages into a single PDF? Use a scanner with an ADF (automatic document feeder) — it scans all pages automatically into one PDF. Alternatively, scan each page individually and use Merge PDF to combine them. Phone scanner apps like Adobe Scan also let you keep adding pages in a single scanning session before saving.

My scanned PDF is too large to email — how do I reduce the file size? A 300 DPI grayscale scan should produce approximately 100–400 KB per page. If your scans are larger (common with color scans at 600 DPI), use Compress PDF to reduce the file size. Most scanned documents compress 50–80% without visible quality loss.

Can I scan to PDF on a Chromebook? Yes. Chromebooks support scanning via the Files app or Google Drive mobile app. You can also use any scanner that supports eSCL (AirScan) protocol over the network.

How do I scan a book without damaging the spine? Use a book scanner (handheld scanning wand) or a V-cradle scanner designed for bound books. Alternatively, photograph pages flat with good lighting and use a scanner app to process the photos. Pressing a book flat on a flatbed scanner can damage the spine of hardcovers.

Is a scanned PDF legally binding? The scan itself is an image of the original document. For legal purposes, a scanned contract signed by all parties is generally treated as a copy of the signed original. For e-signature compliance (eIDAS, E-SIGN Act), use a dedicated e-signature tool to capture signatures digitally rather than scanning wet signatures.