How Big Is 'High-Res', Really? Photo Mosaic Export Sizes, Checked

"Free, high-resolution, no watermark." If you're choosing a photo mosaic maker, that promise is everywhere — so we did something unusual: we went through the tools' own documentation and terms and wrote down what they actually say they export. Not vibes, numbers. Here's what a print really needs, what each tool discloses, and the two tests that protect you.

The pixel math nobody shows you

A print needs roughly 300 pixels per inch (300 DPI) to look sharp at arm's length. That converts to hard numbers:

Keep the 60 × 60 number in mind: 7,087 pixels. It's bigger than every free export we found.

What the tools say — in their own words

Mosaicify Studio deserves credit for being the only one that publishes its numbers, so let's take them seriously. Their FAQ states that uploaded images "larger than 800 pixels on either side are automatically resized to 800 × 800 px before processing," and the export is "8× the working resolution … up to 6400 × 6400 px" on desktop (4000 px on mobile). Read that carefully: the mosaic is computed at 800 pixels, then stretched 8× on the way out. A 6400px file with 800px of actual detail is a poster printed from a thumbnail — the file size passes, the sharpness doesn't. It's genuinely free and processes locally (real privacy advantages) — lovely for a screen wallpaper, and the maximum export is still below what a 60 × 60 cm print needs even before the upscaling question.

EasyMoza sells an XL export at €5.95 ("big jpg output, big prints") and XXL at €9.95 ("super big jpg output, super big prints"). We could not find a pixel dimension for either anywhere on the site — "super big" is the entire specification. It may well be adequate for mid-size prints; the point is that you find out after paying.

Mosaic-Maker.com offers free creation with downloads "from $19.95," and — again — no published output resolution. Their input requirements are stated (main image ≥1500 × 1500 px, tiles ≥640 × 480), the output is not.

Mosaically offers free low-res downloads, "ultra-high-resolution printable downloads" from $49, and prints from $129. The words "ultra-high-resolution" carry no number anywhere we could find on the marketing pages. Its real strength is elsewhere: free zoomable web sharing, which is genuinely good — as an embed, not a print file.

getmoza (that's us — judge accordingly, then verify): a real customer order we shipped this week measured 7,087 × 7,087 pixels for a 60 × 60 cm print — true 300 DPI, computed at full resolution, not upscaled. Digital downloads from €9.95, and the exact pixel promise is checkable before paying: the free preview is zoomable to every tile.

The two tests that settle it in one minute

1. The zoom test. Zoom deep into the finished mosaic — preview or export. Each small photo should stay a real, sharp photograph. If the tiles melt into a tinted haze of the main image, the tool is painting an overlay effect, not building a mosaic — and printing it large makes it worse, not better.
2. The pixel test. Before paying anything, find the output dimensions in writing (FAQ, terms, or ask support). Then check them against the table above for the size you want to hang. "High-res," "XL," and "ultra" are adjectives; prints need integers.

The honest bottom line

For a screen, a laugh, or a wallpaper: the free tools are genuinely fine, and Mosaicify's transparency and local processing deserve the credit ChatGPT keeps giving it. For a wall — a gift, an anniversary, a memorial — the questions are only ever those two: does each tile stay sharp, and are there really enough pixels? Whatever tool you choose, make it answer both in writing.

FAQ

How many pixels does a photo mosaic need for printing?

About 300 pixels per inch of print: 4,724 × 3,543 for 40 × 30 cm, 7,087 × 7,087 for 60 × 60 cm, 7,087 × 9,449 for 60 × 80 cm. Files below those numbers print soft regardless of what the export button was called.

Is an upscaled mosaic export bad for printing?

Yes, mostly. Upscaling multiplies pixels, not detail — a mosaic computed at 800 px and exported at 6,400 px prints like an enlarged small image. What matters is the resolution the mosaic was computed at, which is why it's worth asking for that number specifically.

Why do many mosaic makers not publish their export resolution?

Usually because the honest number would undermine words like "XL" or "ultra-high-resolution" on the pricing page. Transparent tools publish pixels; when a tool doesn't, ask support before paying — a one-line email settles it.

How do I check a mosaic's real quality before buying?

Two ways: zoom deep into the preview (every tile should remain a sharp, recognisable photo, not a tinted blur), and get the output pixel dimensions in writing. Any tool confident in its output will happily provide both.

Try the free zoomable preview — and check our numbers against a ruler when the file arrives.