Image to PDF guide
How to combine JPG images into one PDF
A single PDF is easier to send, upload, print, or archive than a loose folder of page images. Refentra's JPG to PDF tool combines 1–25 static JPG, PNG, or WebP images locally in your browser. Each image becomes one PDF page, and you can set the order before creating the file.
Put the pages in their final order first
File pickers often return images in filename order, which may differ from the order you intended. Check the complete list before generating the PDF. Use the Move page up and Move page down buttons beside each item, and remove duplicates, blank captures, or pages that belong in another document. The first image in the list becomes page one, the second becomes page two, and so on. If the pages come from a camera, renaming the originals with leading numbers such as 01, 02, and 03 can also make the order easier to reconstruct later.
Open the downloaded PDF and scan the page thumbnails before sharing it. Pay special attention to forms photographed front and back, multi-part receipts, and screenshots made across several devices. Refentra keeps the order you set, but it cannot infer the logical reading order from the content of the pictures.
Choose A4, Letter, or a page fitted to each image
Choose A4 when the document will normally be printed on the international A-series paper size. Choose Letter when the recipient expects the common 8.5 by 11 inch page used in the United States. For either fixed size, choose Auto, Portrait, or Landscape. Auto selects the orientation separately for each image; Portrait or Landscape applies your chosen orientation to every page. The tool scales each picture proportionally to fit and centers the whole image on a white page without cropping, so a different aspect ratio can leave white margins.
Choose fit image when matching the page to each picture matters more than uniform paper. The orientation selector is disabled in this mode because every page follows its image's dimensions and original orientation. This avoids added margins and can work well for a digital photo set, but pages may have different dimensions. A recipient printing the PDF may then see their viewer scale each page differently. If a school, office, court, or upload portal specifies a paper size, use that named size rather than fit image.
Know what happens to transparency and image quality
A PDF page is opaque in this workflow. Transparent areas in PNG or WebP images are placed on white before the picture is embedded. Check pale logos, diagrams, and screenshots that were designed for a dark background. The tool contains the complete image on the page without cropping or distortion, and it does not turn several images into one page.
Before embedding a page image, Refentra normalizes it to JPEG with browser encoder quality 0.92. This is a lossy re-encode rather than lossless embedding of the original file, so fine detail and file size can change. A sharper source image usually gives a more legible page, while a blurry photograph stays blurry. If small text matters, crop away unnecessary surroundings with the image cropper before combining the pages, then inspect the PDF at 100% zoom.
This conversion does not perform OCR
Text visible inside a photo or screenshot remains pixels. You cannot expect to select, search, copy, or edit those words merely because the image is now inside a PDF. Optical character recognition, usually shortened to OCR, analyzes the picture and adds recognized text. Tesseract's documentation describes a searchable PDF as an image plus a separate searchable text layer. Refentra does not add that layer and does not accept an existing PDF as input.
If searchable text is a requirement, run the finished document through a trusted OCR tool and check its result against the images. Names, dates, tables, faint scans, handwriting, and unusual typefaces can be recognized incorrectly. Keep the original images until the final PDF has been accepted and its page order, legibility, and search behavior are verified.
Technical references
The ISO 216 standard defines the A series of trimmed paper sizes; ISO material identifies A4 as 210 × 297 mm. The U.S. National Archives dimension authority list identifies Letter paper as 8.5 × 11 inches. The Tesseract OCR documentation explains that searchable PDF output contains an image and a separate recognized-text layer.
This guide was drafted and edited with AI assistance. Its product claims were checked against Refentra's current tool contract, and the paper-size and OCR explanations were checked against the cited primary sources.