A collage is a small piece of layout design: a few rectangles inside a bigger rectangle, each filled with a photo that was not shot for that shape. Most collages that look "off" fail on one of three things: the layout does not suit the number of photos, the cells are a shape that crops the subjects badly, or the spacing is uneven. This article works through each with numbers from the photo collage maker's layout code.
The collage shape decides every cell's shape
Cells are fractions of the canvas, so the canvas shape carries into every cell. Take a 2 × 2 grid:
- On a 1:1 square, each cell is square.
- On a 4:5 portrait canvas (1638 × 2048 at 2048 px), each cell is 4:5 too, about 819 × 1024 before gaps.
- On a 9:16 story (1152 × 2048), each cell is a tall 9:16.
Phone photos are 3:4 in portrait or 4:3 in landscape. A 3:4 photo in a 4:5 cell loses very little (the cell is slightly wider, so a sliver of height is cropped); the same photo in a 9:16 cell loses a quarter of its width. That is why stories suit strips and single columns, and why square grids suit a mix of portrait and landscape photos: a square crops both by the same 25%.
You can compute the loss: a photo of ratio p (width / height) in a cell of ratio c keeps c / p of its width when p > c, or p / c of its height when p < c. A 4:3 landscape photo (1.33) in a square cell keeps 1 / 1.33 = 75% of its width.
Layouts by number of photos
Two photos. A strip side by side (each cell 1:2 on a square canvas, tall and narrow) or stacked (2:1, wide). Side by side suits portraits and before-and-after pairs.
Three. One large on the left taking two thirds of the width, two stacked on the right. On a square canvas the large cell is 2:3, a natural portrait shape, and the two small ones (a third of the width, half the height) are 2:3 as well, so all three crop portrait photos gently. This is the most forgiving three-photo layout.
Four. The 2 × 2 grid: every cell the canvas shape. Nothing competes.
Five and seven. These do not make a full grid. Rows of nearly equal length work (3 + 2, or 4 + 3): the collage maker puts the fuller row first so the eye starts with more detail and ends with larger photos.
Six and eight. Grids of 2 × 3 or 3 × 2, and 2 × 4 or 4 × 2; choose the one whose cells come closest to your photos' shape.
Nine. The 3 × 3 grid is the default, but it makes nine small photos. The framed mosaic, a large centre (half the width and height) with eight around it, gives the collage a subject.
Even spacing
Spacing looks even only when it is exact. If cells are placed by rounding each cell's position and size separately, gaps come out 11 px here and 13 px there, and the eye notices. The collage maker computes each edge from the layout's exact fractions and rounds it once, then insets internal edges by half the gap. Three photos side by side on a 1000 px canvas with an 8 px gap come out 329, 326 and 329 px wide with gaps of exactly 8 px; the outer edges touch the border exactly.
Two practical rules:
- Gap equal to border looks like one continuous mesh. A border larger than the gap (say 40 against 12) reads as a frame or a mat around the collage.
- Corner radius softens the grid but eats into the corners of each photo; keep it under about a tenth of the smaller cell side.
Export sizes
| Destination | Shape | Pixels |
|---|---|---|
| Feed post | 4:5 or 1:1 | 1080 × 1350 or 1080 × 1080 |
| Story | 9:16 | 1080 × 1920 |
| Slide or video cover | 16:9 | 1920 × 1080 |
| A4 print at 300 DPI | A4 | 2480 × 3508 |
Saving larger than the destination only adds file size: a feed shows posts about 1080 pixels wide. For print, A4 at 3508 px on the long edge is 300 DPI.
Common mistakes
- Story shape with landscape photos. A 4:3 photo in a 9:16 cell keeps only 42% of its width. Use a strip of stacked cells, or a square collage instead.
- Faces at cell edges. Drag each photo inside its cell to bring faces toward the middle; zoom in a little if needed.
- Mixing very bright and very dark photos in a tight grid. A wider gap in a neutral colour separates them.
- Too many photos. Nine photos at 1080 px wide are each about 350 px: thumbnails. Pick the five best.
Recipe
- Count your photos and pick the layout: 2 to 4 grid or strip, 3 mosaic, 5 or 7 rows, 9 framed mosaic.
- Choose the shape for the destination, then check how each photo is cropped and drag it into place.
- Gap 8 to 16 px, border the same or larger, white or a colour taken from the photos.
- Export at the destination's size, JPG for photos.
If a photo needs straightening or a tighter crop first, do it in the image crop tool before adding it to the collage maker.