Key takeaways
- A tapered cup unrolls to a curved band, not a rectangle. A rectangle climbs and leaves a V-shaped gap.
- You need three measurements: round the top of the print area, round the bottom, and the height between them.
- Yes, warp the design to the curve, or its top edge will not follow the rim.
- The free tumbler template maker draws the curve and warps the design for you.
“Should I be warping my image or should I not modify it?” is a question r/sublimation asks again and again, usually with a photo of a wrap that has crept up one side. The short answer is yes, and the reason is geometry.
Why doesn't a rectangle fit a tapered tumbler?
A straight tumbler or mug is a cylinder, and a cylinder unrolls to a rectangle: its width is the circumference and its height is the print height. A tapered tumbler is a cone with its tip cut off. Unroll a cone and you get part of a ring: the wide end becomes a long arc, the narrow end a shorter one, and the two sides are straight lines pointing at the ring's centre.
Wrap a rectangle round a cone and it cannot lie flat on both edges at once. It climbs as it goes round, and when the ends meet they meet at an angle, with a wedge of bare cup between them. That is the tilted wrap in every “what did I do wrong” photo.
How do you measure a tumbler for a template?
- Top: wrap a strip of paper round the cup where the top of the design will sit. Mark where it overlaps, lay it flat and measure. That is the top circumference.
- Bottom: the same, where the design ends.
- Height: measure along the side of the cup between the two lines. If you measured straight up with a ruler instead, say so in the tool and it works out the length along the side.
Measure your actual cup. Two “20 oz skinny” tumblers from different makers are not the same shape, and a template for one will not fit the other. If you only have diameters, the tool accepts those too.
How is the curve worked out?
By similar triangles. If the top circumference is C, the bottom c and the height along the side h, the outer radius of the ring is h × C ÷ (C − c), the inner radius is that minus h, and the angle of the band is C divided by the outer radius. The tumbler template maker does this, adds bleed round the edges, and tells you how far the middle of the band sits off a straight line, which is how you know whether the curve matters. When the top and bottom match, it is a rectangle.
Should you warp the design?
Yes, for a tapered cup. Your design's top edge has to follow the curved top of the template, so the artwork has to be bent to the same arc: the left edge of the design to one end of the band, the right edge to the other, the top to the rim. Drop the design on the template maker and it does this warp at 300 dpi, either stretching the design to fill the wrap or keeping its proportions centred.
For a repeating design that goes all the way round, make sure the pattern's left and right edges match, or the join shows. The seamless pattern maker checks and fixes that.
What should you check before printing?
- Print the template on plain paper at 100% (“actual size”, not “fit to page”), cut it out and wrap it round the cup. It should meet itself neatly and follow the rim.
- Mirror only if your setup needs it. Many sublimation workflows mirror in the printer software; mirroring twice prints backwards. Test once.
- Check the sheet size. A curved wrap is taller than the print height. The tool lists which papers it fits, from Letter to 13×19 in.
- Leave room for a handle. Set coverage under 100% for a mug or a handled tumbler.
Sources
- OnlineLabels: tapered label generator — the same three measurements, for labels; read 21 September 2026.
- r/sublimation threads read 21 September 2026: “Warping designs to make tapered tumblers?” and “Questions about creating a sublimation template for this tumbler”.
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