---
title: "Dot-to-Dot Puzzle Maker from Any Picture | Puzzle Dotter"
description: "Turn a photo or drawing into a printable dot-to-dot with numbered dots, a start star and an answer key. Free, and your pictures never leave your device."
url: https://puzzledotter.lol/
---

Dot-to-dot maker

# Turn a picture into a dot-to-dot puzzle

Pick a sample or drop in your own picture. Puzzle Dotter traces the main shape, spreads numbered dots along it and lays out a printable page with an answer key. Your picture is processed on this device and never uploaded.

## How to make a dot-to-dot that works

1. **Pick one clear subject.** A pet against a plain wall, a clip-art animal or a drawing on white paper. Cut-out PNGs with a transparent background work best.
2. **Check the outline.** The Outline tab draws the traced shape in red. If it hugs the background, try another Shape is setting or move Sensitivity.
3. **Choose the number of dots.** As a rough guide, 15–25 dots suit preschoolers, 30–60 early readers, and 100 or more makes a slow, satisfying puzzle for older children and adults.
4. **Print the puzzle and its answer key**, or download either as PNG or SVG.

### What the settings do

**Follow the shape** keeps dots on corners such as ears, fins and points, then spaces the rest evenly; **Evenly spaced** puts the same distance between every pair. **Smoothing** rounds off a ragged outline from a photo. With **Automatic** number size, numbers grow as large as the gaps allow, and each one is placed where it overlaps no dot, number or connecting line.

### How the shape is found

The background colour is read from the picture's edges and every pixel is compared with it in CIELAB colour. Otsu's method sets the cut-off, the largest solid piece becomes the shape, its border is traced, and Visvalingam–Whyatt simplification finds the corners. Busy photo? Use **Edit dots by hand**.

## Sources

- Otsu N. A threshold selection method from gray-level histograms. *IEEE Transactions on Systems, Man, and Cybernetics* 1979;9(1):62–66. [doi:10.1109/TSMC.1979.4310076](https://doi.org/10.1109/TSMC.1979.4310076)
- Suzuki S, Abe K. Topological structural analysis of digitized binary images by border following. *Computer Vision, Graphics, and Image Processing* 1985;30(1):32–46. [doi:10.1016/0734-189X(85)90016-7](https://doi.org/10.1016/0734-189X(85)90016-7)
- Visvalingam M, Whyatt JD. Line generalisation by repeated elimination of points. *The Cartographic Journal* 1993;30(1):46–51. [doi:10.1179/000870493786962263](https://doi.org/10.1179/000870493786962263)
- CIE. *Colorimetry, 4th edition* (CIE 015:2018), for the CIELAB colour space. [doi:10.25039/TR.015.2018](https://doi.org/10.25039/TR.015.2018)

## More printables from your pictures

Three more makers for rainy afternoons, classrooms and art practice.

- [Paint by numbers generator](https://puzzledotter.lol/paint-by-numbers-generator/): Your photo as numbered areas with a colour key, a cleaned-up palette and a preview of the finished painting.
- [Colouring page maker](https://puzzledotter.lol/colouring-page-maker/): Clean black line art from a photo, with controls for detail, line thickness and stray specks.
- [Grid drawing method](https://puzzledotter.lol/grid-drawing-method/): A numbered, lettered grid over your picture plus a matching blank grid, to copy or enlarge it square by square.

## Recommended

Two free services for the online side of finding printables.

Temporary email · no sign-up

### CleanTempMail

Plenty of worksheet and printable sites ask for an email address before the download starts, and then send newsletters for months. CleanTempMail gives you a free disposable inbox straight away, with no sign-up, a random or custom address on hundreds of domains, and messages deleted automatically after 3 days.

[Open a temporary inbox](https://cleantempmail.com/)

Disposable cloud browser

### WebTraceCheck

Found a "free colouring pages" site you have never heard of, full of pop-ups and download buttons? Open it in WebTraceCheck's disposable cloud browser instead: it runs on an isolated Linux desktop that is deleted after each session, with nothing to install and free time every day.

[Try the cloud browser](https://webtracecheck.com/)

## Questions

**Is my picture uploaded anywhere?**

No. Your browser reads the file and a background worker on your own device does the tracing. Nothing is sent to a server.

**Why are the numbers small?**

Automatic picks one size for the whole page from how close the dots are. For bigger numbers, use fewer dots or choose Large.

**Can I make a puzzle without a picture?**

Yes. Switch on Edit dots by hand, press Clear all and click to place dots in order: a letter, a number, a star or a child's own design. The faint picture behind the dots is only a guide while you edit; it is never printed.

**Can I share the puzzles I make?**

The pages are yours to print and hand out. If you start from someone else's photo or artwork, their copyright still applies, so use your own pictures or ones you have permission to use.