OneTaskBy Tim King · Updated
String Art Generator
Nail and Thread Art From a Photo, With a Numbered Sequence to Follow
OneTask is free, with no sign-up, and built by one person.
If this tool saved you time, a coffee helps keep new ones coming.
How the String Art Generator works
This string art generator plans a thread path round nails. String art builds a picture from a single unbroken thread stretched between nails around a frame. Drop in a portrait or any high-contrast photo and this tool plans that thread for you: it places the nails, chooses every line in order, previews the result at full size and gives you the numbered nail sequence to wind it by hand. Nothing is uploaded.
String art generator: how the thread is planned
The image is centred and cropped to the frame, converted to a map of darkness, and the nails are spaced evenly around the edge. Starting at nail one, the planner looks at every nail it could go to next, measures how much unclaimed darkness lies under the straight line to each, and picks the darkest. That line is drawn, the darkness beneath it is reduced so the next line is not attracted to the same place, and the search repeats from the new nail until the line count is reached. The result is a greedy path, not a globally optimal one, but it is the method used by almost every hand-built string art project and it reads well at a distance because the eye blends the crossing threads into tones.
Nails and lines
More nails give the thread more angles to choose from and let it follow fine edges; 200 to 300 is the usual range for a portrait. More lines darken the image: a few hundred give a faint sketch, two thousand a solid mid-tone portrait, four thousand a dense, dark piece. The Thread setting changes how much darkness each line is assumed to remove, which mimics thinner or thicker thread. Light thread needs more lines to reach the same tone and holds more detail; heavy thread fills faster and looks bolder. The preview draws each line with matching transparency so the on-screen tone is a fair guide to the finished piece.
Frame shape
Circle is the classic hoop or round board and suits faces, because the corners of a photo rarely hold anything important. Square keeps the whole image and numbers the nails clockwise from the top-left corner, spreading them evenly along the four sides.
Building it
Switch Download to Nail sequence to get a text file: one nail number per line, starting at nail one, which is at the top of a circle or the top-left corner of a square, with numbering running clockwise. Wind the thread from each nail to the next in that order. The Thread stat estimates how much thread a frame one metre across needs; scale it to your frame size. A 240-nail, 2000-line portrait on a 60 cm hoop typically uses around 700 metres of sewing thread, so buy a full reel.
What images work best
A portrait with a plain, light background, strong lighting and a dark side to the face gives the best result, because string art can only add darkness to a white ground. Busy backgrounds turn into a grey haze. If a photo comes out muddy, raise the contrast before dropping it in, or crop tighter to the face.
FAQ
Why does the preview look grey and washed out?
Each line is drawn semi-transparent to match real thread, so a single line barely shows and tone builds up where lines cross. Increase Lines or switch Thread to Heavy for a darker image, and use a photo with strong contrast so the planner has clear dark areas to aim at.
How long does the planner take?
A few seconds for the default settings. The time grows with both nails and lines, because every line considers every nail, so 360 nails and 4000 lines can take ten seconds or more on a slow laptop. The page stays responsive once it finishes.
Can I use colour thread?
The planner works in black on white, which is how the vast majority of string art is made. For a colour piece, split the photo into separate channels with an image editor, run each one here and wind each colour in turn, darkest first.
Which nail is nail one?
On a circle it is the nail at the very top, with numbers increasing clockwise. On a square it is the top-left corner, running clockwise along the top edge first. The nail sequence file restates this so it can be printed and used away from the screen.
See also: all Images tools, Audio, Video & Screen, PDF, SVG, Simulations & Screensavers, Generative Art, Chart Makers, 3D Model Viewers, Drawing Pads, Mockups & 3D Making, Diagram Makers, 3D Science, Tracker Music.
Related tools
Image To ASCII Art
Turn a photo into ASCII art at any character width.
Pixel Art Upscaler
Enlarge sprites 2× to 32× without blurring the pixels.
Palette Extractor
Pull the dominant colours out of a photo as hex codes.
Halftone Generator
Turn a photo into a halftone dot screen in black, white or CMYK.
Image Dithering Tool
Dither a photo with Floyd-Steinberg, Atkinson or ordered Bayer patterns to a few colours.