A column of pictures, one file
Stacking images vertically is how receipts, chat threads, recipe steps, comic panels and product details are shared: one picture you scroll down, in order. This page opens with the direction fixed top to bottom and the widths matched, so adding pictures is the only thing you have to do. Everything else — the order, the gaps, the joins — is there when you want it and out of the way when you do not.
The awkward part of a vertical merge is the height. Ten phone screenshots make a picture over twenty thousand pixels tall, which some browsers cannot draw and every chat app will shrink. So this page forecasts the finished size before drawing anything, says how many phone screens tall it is, and offers to save it in readable parts.
What the defaults are, and why
- Matched to the narrowest. A wider picture is scaled down to the narrowest one’s width. Scaling down keeps detail sharp; scaling the narrow ones up would make them soft.
- Edge to edge. No gap and no border. The pictures touch, which is what most people mean by merging.
- Order by name. Phones name screenshots and photos by time, so name order is usually the order they were taken. Drag a thumbnail, or use the arrows, to move one.
- One file. Parts are offered, not forced; the forecast tells you when they would help.
A worked example
Three photos: 1080 × 1350, 1200 × 900 and 1080 × 1080. The 1200-pixel photo is scaled to 1080 wide, becoming 1080 × 810, so the stack is 1080 × 3240 pixels — exactly three 1080 × 1080 squares tall, or about 1.7 phone screens. That fits in one part at 4,096 pixels. Add six more photos of the same kind and the forecast passes 9,000 pixels; Save in parts then writes three files of up to 4,096 pixels, each repeating 60 rows of the one before.
Privacy, specifically
The pictures are read and joined inside this tab, and only the file you save leaves it. Tall stacks are often chats and bills, so the Save step also has solid boxes you can draw over names, numbers and faces before saving — solid, never blurred, because a blur can be reversed.
The column is limited by what this browser can draw in one piece — about 32,767 pixels tall on a desktop, much less on an iPhone. Scaling to the narrowest makes a very narrow picture shrink every other one with it; remove it or choose another fit if that happens.
Stacking images: the usual snags
My images are different widths. What happens?
They are all scaled to the narrowest one, so nothing is enlarged and nothing goes soft. If you would rather keep the widest at its size, open the Fit step and choose Match the biggest; to keep every picture exactly as it is, choose Leave them alone and the narrower ones get a band of ground colour beside them.
How tall can the merged image be?
Most desktop browsers draw up to 32,767 pixels on a side; iPhones and iPads stop far earlier, around 8,192. The Save step forecasts the finished height before anything is drawn. If it is past what this browser can draw, fit the output to a narrower width or merge in two batches.
Why does WhatsApp make my tall image blurry?
Chat apps shrink a very tall picture until its long side fits their limit, and small text becomes unreadable. Turn on Save in parts: the column is cut into parts no taller than 4,096 pixels (or one 9:16 screen), each repeating a few rows of the last so nothing falls in the gap, and numbered part-1-of-3 onwards.
Can the images overlap instead of just touching?
Yes. In the Seams step each join can overlap and fade, and Find the overlaps looks for the rows two pictures share — useful for screenshots of one page. For phone screenshots with a status bar and a menu on each, the long-screenshot tool removes those repeated bands for you.
Is there a gap between the images?
Not unless you add one. They touch edge to edge by default; the Fit step adds an even gap in pixels, a divider line in a colour you choose, rounded corners and a border.
