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MakeMyStickers
MakeMyStickers

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I Built a Free Sticker Maker Because Every Other One Hid the Export

Every "free" sticker and label maker I tried did one of three things: forced a signup, stamped a watermark on the export, or hid the actual download behind a trial. I just wanted to drop some images onto an Avery-compatible template and print them. So I built MakeMyStickers, with no account, no watermark, no email, and everything running client-side.

Here are the parts that were actually interesting to build.

Print accuracy is a millimeter problem, not a pixel problem

Avery-compatible templates (5160, 8160, 5163, 5167, etc.) are defined in real-world dimensions: label size, margins, pitch, and gaps in millimeters. Screens think in CSS pixels. So the whole layout engine works in mm internally and only converts to pixels at the very end.

For export, that means rendering the full sheet to a canvas at print resolution:

const DPI = 300;
const canvasW = Math.round(paper.wMM / 25.4 * DPI); // mm -> inches -> px
const canvasH = Math.round(paper.hMM / 25.4 * DPI);
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At 300 DPI an 8.5x11" sheet is about 2550x3300px. Get the mm-to-px conversion wrong by a hair and every label drifts off its die-cut line, which on a 30-up sheet is very visible.

Generating the PDF on the client

No server round-trip. I render the sheet to a canvas, encode it as a JPEG, and embed it into a PDF with pdf-lib:

const blob = await new Promise(resolve =>
  sheetCanvas.toBlob(resolve, "image/jpeg", 0.92)
);

const doc = await PDFDocument.create();
// embed the image at exact page dimensions, then save
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Because the page size is set from the real paper dimensions, the PDF prints 1:1, with no "fit to page" scaling that would throw off alignment.

Text that actually fits the label

Auto-sizing text to a fixed label width is deceptively annoying. I dropped the old "average character width x 0.55" guess and used the canvas's real metrics:

const ctx = document.createElement('canvas').getContext('2d');
ctx.font = `${size}px ${family}`;
const realWidth = ctx.measureText(label).width;
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Measuring the actual rendered width (per font and weight) means the text fills the label without overflowing the die-cut edge.

Bonus: transparent PNGs for Cricut Print-Then-Cut

For cut machines I export a transparent PNG instead, crop the canvas to its alpha bounds, and size it to the machine's printable area so it imports at the intended physical dimensions.

Try it

It's free and runs in the browser. Try it at makemystickers.app if you ever need to print labels or stickers. Happy to answer anything about the canvas/PDF pipeline in the comments.

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