Print preparation is a short list of jobs: crop to the ordered ratio, resize to the print size, sharpen once, export in sRGB with the profile embedded. Any of the tools below does all four. The differences are how they handle raw files, how much they cost, and whether they run in a browser.
Free, and enough for most people
GIMP does everything on the list and has for years. Its interface is its own and takes an afternoon to learn, but cropping, resizing, unsharp mask and export to JPEG with a colour profile are all there. Photopea runs in the browser, opens Photoshop files, and needs no installation; it is the tool to use on a borrowed computer. For raw files, Darktable and RawTherapee are free and serious, and both export to sRGB JPEG with the profile embedded.
Affinity, from Canva, is the surprise on the free list: Affinity Photo, Designer and Publisher were combined into one free application in late 2025. It is a professional tool, it handles raw, layers and CMYK, and it is what we would put on a new computer first.
Paid, and worth it for a reason
Adobe Lightroom and Photoshop are the subscription that most photographers already have; if you do, use them and skip this section. The paid alternatives each earn their price on one thing. DxO PhotoLab has the best lens corrections and noise reduction we know of, which matters when a print is large and the file was shot at high ISO. Luminar Neo from Skylum does sky replacement, relighting and other one-click edits that would take an hour by hand. MAGIX Photo & Graphic Designer is a Windows program that combines photo editing with page layout, which suits a poster with text on it.
Posters and anything with type
A photo editor is the wrong tool for a poster with words on it, because type in a photo editor is pixels, and pixels at A1 look soft. Use a layout or vector tool: Affinity Designer or Publisher, Inkscape (free), or Canva for a quick job. These export a PDF with vector type, which stays sharp at any size and is what commercial printers such as Onlineprinters ask for. Our poster guide covers sizes, bleed and the export settings.
Phones
A phone can prepare a print if the file is good enough to begin with. Snapseed (free) crops to a ratio, sharpens and exports at full size. Lightroom’s mobile app does the same and syncs to the desktop. What no phone app does well is show you pixels per inch against a print size, so check that on a computer before ordering anything above A3.
The setting that ruins most home prints
It is not the software. It is the monitor’s brightness. A screen at full brightness makes every photo look lighter than it will print, and the print comes back dark. Turn the monitor down to something close to the room’s light, and if you print often, a calibration device pays for itself in the first wasted large print it prevents.