DTF halftones explained: when to use them and which LPI to pick

Screen printers have used halftones for a century. DTF printers are catching on, for good reason: a halftone fixes problems DTF otherwise can't, and it makes the transfer feel noticeably better on the shirt.

What a halftone actually is

A halftone replaces tone with dots. Instead of a pixel being "60% grey" or "40% transparent", the area is filled with solid dots that cover 60% or 40% of it. Up close you see dots; from arm's length your eye blends them into a smooth tone.

For DTF that matters because the printer can't print partial transparency. Every semi-transparent pixel gets full white underbase. Solid dots print exactly as intended.

When to halftone a DTF transfer

1. Fades, glows and soft shadows. The most common reason. A gradient fade or drop shadow prints as a cloudy box; as dots it prints clean and still reads as a fade. You can halftone only those soft areas and leave the rest solid.

2. Large solid designs. A full-back print in solid ink is a heavy, rubbery patch that doesn't breathe and can crack. Halftoning the whole design lets the fabric flex between the dots. The print feels softer, lighter and more like a screen print.

3. Vintage and screen-print looks. Visible dots are a style in themselves: comic, retro, 70s and 80s band tees.

4. Less ink. Fewer inked pixels means less ink, powder and film per transfer. On long runs it adds up.

When not to: small text, thin lines, and tiny logos. There isn't enough area for dots to describe the shape.

Which LPI to use

LPI (lines per inch) is how many rows of dots fit in an inch. Lower is bigger, more visible dots; higher is finer and smoother.

• 20 LPI: chunky, deliberate vintage or comic look.
• 25–35 LPI: the sweet spot for most DTF printers. 35 is a good default.
• 45–55 LPI: smooth fades, but only on printers with very good dot control.

LPI is physical, so it depends on print size. Always set the real print width before choosing.

The print-safety part nobody mentions

Dots have a lower size limit. A DTF dot needs enough adhesive powder to bond. Dots under about 0.4–0.5 mm across often don't transfer, or wash off after a few cycles. A good halftone:

• Never prints a dot smaller than that. Tiny dots are either raised to the minimum or dropped.
• Allows for dot gain. Ink spreads slightly on film and under the press, mostly in the midtones, so dots are drawn a little smaller to compensate.
• Goes solid above a maximum. Past about 85% coverage the gaps between dots are too small to survive pressing, so the area should simply print solid.

Our free DTF halftone generator applies all three automatically, shows the dot size in millimetres at your print width, and warns you if your settings go below the safe dot size.

Test before a full run

Settings that look right on screen aren't proof. Print a test strip (a ramp from 0% to 100% at your exact settings), press it on scrap fabric, and wash it a few times. If the light end of the ramp loses dots, raise the smallest dot or lower the LPI.

The halftone generator has a Download test strip button that makes a labelled 6-inch strip with your exact settings.

How to halftone a design in a minute

1. Open the halftone generator and choose your print size.
2. Pick Full design for a soft screen-print feel, or Fades & shadows to fix only the soft areas.
3. Choose ink level and dot size; zoom to "Actual size" to see the real dots.
4. Download the PNG. It's free, no account, and the file never leaves your device.

Want a worn look too? Distress first with the distressed effect generator, then halftone the fades.

Questions

Is a halftone the same as lowering opacity?

No, and that's the point. Lower opacity gives you semi-transparent pixels, which DTF prints as white haze. A halftone keeps every pixel fully solid or fully clear and carries the tone in dot size.

What angle should DTF halftone dots be?

22.5° is the usual choice: it hides the grid well and avoids patterns with fabric weave. 45° is classic. 0° gives a visible grid, which can be a deliberate style.

Should I turn off halftoning in my RIP?

Yes, for a file that's already halftoned. Halftoning twice causes moiré, a wavy interference pattern.

Will halftone dots wash off?

Not if they're above the minimum size and pressed correctly. Small dots are the ones at risk, which is why a safe minimum dot size matters more than anything else.

Does halftoning work on white shirts?

Yes. Choose which tones drop out to the shirt: dark areas drop out on dark shirts, light areas on light shirts.