Grid layouts and free layout
Each number of photos has its own set of grids: equal rows and columns, one large photo with the others beside or below it, and mixed rows such as two on top and three below. The grid fills the whole picture, and every box is filled edge to edge with its photo, cropped from the centre at first. The spacing slider sets the gap between boxes and the border slider the margin around the outside; both are measured against the size of the collage, so a design looks the same at 1080 pixels and at A4 print size. "Free layout" works like photos laid on a table: each photo keeps its whole picture and its own shape, you drag it anywhere, pull its corner handle to make it bigger or smaller, and tap it to bring it to the front. In free layout the border slider becomes a white photo frame with a soft shadow.
Framing every photo: drag, zoom and swap
Faces near the edge of a photo are often cut off by a grid. Drag a photo inside its own box to slide it until the right part shows; it stops at the edge of the picture, so no empty strip appears. Select a photo and use the zoom slider, or the mouse wheel, to enlarge it up to four times. To change the order, drag a photo out of its box and release it over another: the two swap places, each keeping its own framing. The "Move earlier" and "Move later" buttons do the same without dragging, and with the preview selected the arrow keys move the selected photo and the + and - keys zoom it, so the tool can be used with a keyboard.
Sizes: square, story, A4 print or your own
Square is 2160 × 2160 pixels. Story is 1080 × 1920 pixels, the 9:16 shape Instagram recommends for stories; 4:5 portrait (1080 × 1350) and 16:9 landscape (1920 × 1080) are there for posts and screens. Instagram's publishing rules accept feed pictures between 4:5 and 1.91:1 and scale anything wider than 1440 pixels down, so the larger square still looks sharp after upload. For printing, A4 is 2480 × 3508 pixels, which is 210 × 297 mm at 300 dots per inch, the usual resolution for photo prints. Custom sizes go from 200 to 8000 pixels per side and up to 40 megapixels in total, which most browsers can draw.
Saved at full quality, with no watermark
The collage is drawn again from your original photos at the size you chose, not copied from the small preview, and nothing is added to it: no logo, no text, no watermark. JPG at 95% quality is the default, a good balance of sharpness and file size; choose 100% for the largest, most detailed file, or PNG for a lossless picture that is bigger again. Each photo is used at up to 4000 pixels on its long side, more than any box in the largest sizes needs, which keeps memory use safe on phones. Phone photos are turned the right way up first. Because the collage is a new picture, the camera data of your photos, such as GPS location, is not copied into it. To make the file smaller for an upload form, use Compress image.
Private by design, and which photos open
Your photos are decoded and drawn by your own browser, and the finished collage goes straight to your downloads; nothing is sent to a server and there is no account. JPG, PNG, WebP, GIF and BMP photos open in every current browser. iPhone HEIC photos open only in browsers that can read HEIC, such as Safari; elsewhere, convert them first with HEIC to JPG. To put photos into a PDF instead of one picture, for example receipts for an expense claim, use JPG to PDF, which keeps each photo on its own page.