Halftone Generator for DTF & Screen PrintingNew
Turn a photo or design into halftone dots, ellipses or lines with real control over LPI, angle, levels and dot size — preview it on a shirt colour, then export a transparent 300 DPI PNG or SVG.
Runs in your browser — your image is never uploaded.
How to make a halftone for DTF or screen printing
Short answer: drop in your image, pick an LPI that matches your process (35–45 for most screen printing, start low and test for DTF), keep the angle at 22.5° or 25°, tune the shadow/highlight cutoffs and dot size until it reads clearly, then download a transparent 300 DPI PNG or an SVG.
- Drop a photo or design. Both work — everything is converted to grayscale first, so colour photos halftone the same way flat art does.
- Pick LPI and angle. LPI (lines per inch) sets how fine the dot pattern is; angle rotates the dot grid to avoid a wavy moiré pattern against the mesh or printhead.
- Set the levels. The shadow cutoff is the darkest tone that gets a full-size dot; the highlight cutoff is the lightest tone that gets no dot at all. Move them until the midtones look right.
- Cap the dot size. Max dot size stops neighbouring dots merging into a solid blob in the darkest areas; min dot size stops the lightest areas producing dots too small to print.
- Check the garment preview. Click through the swatches — white, black, navy, grey, red — to see how the transparent halftone will actually look printed.
- Download. The PNG is always available at 300 DPI; the SVG only appears for coarser halftones (45 LPI or under) where the shape count stays manageable.
What LPI means, and what to use
| Use | Typical LPI | Why |
|---|---|---|
| Screen printing — simple / cartoon art | 35–45 | Coarser dots hold up reliably through a mesh screen and multiple wash cycles. |
| Screen printing — manual press | ~55 | Manual registration has more variance, so a mid-range LPI balances detail and reliability. |
| Screen printing — automatic press | up to 65 | Automatic presses register more precisely, so they can hold a finer screen. |
| DTF | no single number | Depends on printer, film, RIP and powder — print test swatches across a range and pick the finest one that survives pressing and washing. |
LPI (lines per inch) is the spacing of the halftone's dot grid — the same idea as DPI, but measured in dot rows, not printed pixels. A higher LPI packs the dots closer together for a smoother-looking gradient, but each dot also has to be reproduced more precisely by your printer, screen mesh or press — which is why print methods with more variance (a hand-pulled screen print, an inconsistent DTF setup) use a coarser (lower) LPI, and more controlled methods can push finer (higher).
Why the angle matters
A halftone's dots sit on a regular grid, and so does your screen's mesh (its threads) or a printer's raster pattern. When two regular grids overlap at a small angle to each other, they create a visible wavy interference pattern called moiré — it isn't in your artwork, it's an optical side-effect of two grids nearly-but-not-quite lining up. Rotating the halftone grid to 22.5° or 25° (rather than a "clean" 0° or 90°) keeps it far enough from the mesh's own grid lines that the interference stays invisible. 45° is a common practical starting point for a single-colour DTF halftone too — but if you ever see a moiré pattern in a proof, changing the angle a few degrees is usually the fix, for either method.
Dark-garment printing
This tool always exports a transparent PNG (or SVG) with dots in a single ink colour — it never bakes in a garment colour, so the same file works for any shirt. For a dark garment: set the ink colour to white (or your ink), and if your source photo is dark subject on a light background, tick Invert tones so the halftone represents where ink prints (the subject) rather than the light background. If your file already has a black or white rectangle behind the design that isn't part of the art, use Knock out background first so it doesn't get halftoned along with everything else.
Common mistakes
- Using photo-quality LPI on a screen print. A 65+ LPI halftone looks great on screen but can clog a mesh screen or wash out — match the LPI to your actual print method, not to how it looks on your monitor.
- Leaving the angle at 0°. A straight horizontal/vertical grid is the most likely to moiré against a mesh — 22.5° or 25° is safer.
- No max dot size. Shadows fill in solid and the halftone texture disappears in the darkest areas.
- Forgetting to preview on the garment colour. A halftone that reads fine on a white background can vanish or look muddy on a mid-tone shirt — always check the swatches.
- Requesting SVG on a fine, large halftone. Above 45 LPI a normal image can produce well over 40,000 individual shapes — the PNG is the right format there.
FAQ
What LPI should I use for screen printing?
35–45 LPI for simple, cartoon-style art; 55 LPI for a manual press and up to 65 LPI for an automatic press, which holds registration more precisely. Coarser (lower LPI) prints more reliably through a mesh screen; finer (higher LPI) looks smoother but is more likely to clog or lose dots on press and in the wash.
What LPI should I use for DTF?
There's no single correct number — it depends on your printer, film, RIP software, powder and press, so DTF shops typically start at a low-to-moderate LPI, print a test swatch across a few settings, and pick the finest one that survives printing, pressing and a wash test. Starting around 35–45 LPI and adjusting from there is a reasonable default.
What angle should I use for a halftone?
22.5° or 25° are the standard choices for a single-colour halftone — they keep the dot rows from lining up with a screen's mesh threads or a printhead's pass lines, which is what causes visible interference patterns. 45° is a common practical starting point too, especially for DTF, but it isn't a universal rule — if you see a wavy moiré pattern, try a different angle.
Why do my halftone dots need a minimum and maximum size?
Without a floor, the lightest areas produce dots too small to print or press reliably and effectively disappear. Without a ceiling, the darkest areas grow dots until neighbouring dots touch and merge into a solid patch, losing the halftone texture (and, in screen printing, risking the screen filling in). Capping both keeps the darkest and lightest areas printable.
How do I make a halftone for a dark shirt?
Set the dot colour to white (or your ink colour), and if your source image is dark art on a light background, turn on “Invert tones” so the halftone represents where ink should print rather than where it shouldn't. If your source file already has a black or white rectangle behind the design that isn't meant to print, use “Knock out background” to make it transparent first.
Round, ellipse or line halftone — which should I pick?
Round dots are the standard, most forgiving choice. Elliptical dots were the traditional choice for offset printing because they merge more gradually through midtones, giving a smoother tonal transition — some printers still prefer the look for portraits. Line screens (parallel lines instead of dots) give a distinct retro, engraved look and read well at a distance, but hold less fine detail.
Does my image get uploaded anywhere?
No. The halftone is built entirely on your device with the Canvas API — nothing is sent to a server, and the tool is free with no sign-up or watermark.
Why is SVG not available above 45 LPI?
A halftone at 45+ LPI on a normal-sized image can mean tens or hundreds of thousands of individual dots. An SVG with that many shapes is slow to open, slow to edit and often larger than the equivalent PNG, so the tool only offers it for coarser, lower-shape-count halftones where a vector file is actually practical.
Sources
Checked 29 September 2026:
- ScreenPrinting.com, A Crash Course in Halftones for Screen Printing — 35–45 LPI for cartoon-style art, 55 LPI manual press, up to 65 LPI automatic press.
- DTF Dallas, DTF Halftone Software and Photoshop Guide — no universal DTF LPI; test swatches across settings and pick the finest that survives production.
- t-biznetwork, Halftone Dots Made Easy — 22.5°/25° angle recommendation for single-colour halftones to avoid mesh interference; 45° as a practical DTF starting point.