What This Tool Does
This tool bridges images and PDFs bidirectionally. In 'Image → PDF' mode, upload multiple JPG/PNG images and they'll be combined into a single PDF with one image per page, at your chosen page size. In 'PDF → Image' mode, upload a PDF and each page is rendered to a PNG image you can download individually.
Inputs Explained
- Direction: Image → PDF or PDF → Image.
- Files: For Image → PDF: multiple JPG/PNG. For PDF → Image: a single PDF file.
- Page Size: For Image → PDF: A4, Letter, or Fit-to-image.
- DPI: For PDF → Image: higher = sharper but larger files.
How It Works
Image → PDF uses the pdf-lib library to create a new PDF, embed each image, and add one page per image sized appropriately. PDF → Image uses pdf.js to render each page at your chosen DPI onto a Canvas, exported as PNG. Both libraries run entirely in your browser.
Formula / Logic Used
Image to PDF & PDF to Image Converter
Combine images into a PDF or extract PDF pages as images — all in your browser.
Step-by-Step Example
Image → PDF workflow:
- Select multiple JPG or PNG files (they'll appear in file order).
- Choose A4 or Letter page size — images auto-scaled to fit with margins.
- Download the combined PDF (typically 200-800 KB for 5-10 photo pages).
PDF → Image workflow:
- Upload a PDF (up to ~50 MB).
- Each page renders as a PNG thumbnail.
- Click 'Download PNG' on any page, or use the cards to extract individual pages.
Use Cases
- Scan-to-PDF: Combine phone photos of documents into a single PDF for emailing.
- Receipt compilation: Merge expense receipts (JPG photos) into one PDF for accounting submission.
- PDF page extraction: Pull specific pages from a PDF as images for use in presentations or documents.
- Contract conversion: Turn signed paper documents (photographed) into properly formatted PDFs.
- Portfolio PDFs: Combine design mockups into a single shareable PDF without using Photoshop or Acrobat.
Assumptions and Limitations
- PDF generation uses pdf-lib which supports standard features — advanced PDF features (forms, encryption, bookmarks) are not added.
- Very large PDFs (>50 MB) may exhaust browser memory. For huge files, use a desktop tool.
- Text in rendered PDF images is no longer searchable — it becomes pixels. For searchable text output, use OCR tools.
- PDF→Image currently uses PDF.js which may render some complex PDFs (with unusual fonts or embedded media) imperfectly.
Frequently Asked Questions
What's the maximum file size I can process?
Browser memory is the main limit. Typically 20-50 MB PDFs and combining up to 50-100 images works on modern devices. Very large collections may slow down or fail on older phones.
Can I reorder images before creating the PDF?
Currently, images are processed in the order they appear in the file picker (usually alphabetical by filename). Rename your images with prefixes (01_, 02_) to control order before uploading.
What's the quality of images extracted from PDFs?
Controlled by the render scale slider (1×-4×). 1× matches the PDF's native resolution (usually 72 DPI), 2× produces 144 DPI (recommended), 3× for printing, 4× for maximum quality with larger file sizes.
Can the output PDF be password-protected?
No. This tool creates unprotected PDFs. For password protection, open the output in Adobe Acrobat or use a desktop tool like Apple Preview (Mac) or PDFsam.
Does it preserve image quality in the PDF?
JPGs are embedded as-is (no re-encoding, so quality is preserved). PNGs are embedded with their original lossless data. No quality loss happens during Image → PDF conversion.
Can I combine PDFs together?
Not in this tool. This handles image↔PDF conversion. For merging multiple PDFs, use a dedicated merge tool, or open each PDF here and combine the extracted images into a new PDF.
Is my file uploaded to a server?
No. All PDF creation and rendering happens in your browser using pdf-lib (for creating) and PDF.js (for reading). Files are processed locally and never leave your device.
Why is the PDF larger/smaller than expected?
PDF size depends on image compression. Pre-compress large JPGs with our Image Compressor before combining for smaller PDFs. Already-compressed JPGs produce efficient PDFs — huge uncompressed source images bloat the output.
Sources and References
- pdf-lib — JavaScript library used for PDF creation, embedding images.
- PDF.js (Mozilla) — Library used for PDF rendering in the browser.
- ISO 32000 — PDF Specification — Official PDF file format standard.
- MDN — Canvas Rendering — Browser API used for rendering PDF pages to images.