Rabbits across the country can rest easier.

A groundbreaking lab in Boston is growing human skin to sell to companies for cosmetics testing.

MatTek Corp. collects skin cells from surgical waste and treats them like seeds, growing small patches of skin that look more like dollops of jello.

Area hospitals give excess skin — with a patient’s permission to donate for research — to MatTek from procedures including circumcisions and tummy tucks. The lab also receives samples from deceased donors through the National Disease Research Interchange.

Creating a layer of skin tissue from a petri dish of cells is a careful process that takes several days of precise measurements to ensure the replication creates a sample that works just like the skin on your arm. A blood substitute soaks the cells from the bottom, and air stirs it from the top.

MatTek grows skin of all sexes, races and ages — but you’d never know.

“You wouldn’t be able to tell the difference from just looking at them,” MatTek President Mitch Klausner told Wired.

The company then ships the new skin to cosmetic companies across the country, providing a long-awaited substitute for animal testing.

“They are a much better simulation of human skin than animals are,” Carol Treasure told Wired. Her company uses MatTek’s skin to test products for companies including Lush Cosmetics.

In the past, companies like Treasure’s XCellR8 would use rabbits to test the toxicity of chemicals in cleaning products, makeup and anti-aging creams. Technicians would shave off patches of the rabbit’s fur and apply whatever product needed testing.

The European Union banned the practice of testing cosmetics on animals in 2013, and PETA’s been fighting against testing on rabbits since 1988.

But with MatTek’s samples, a company can simply add a drop of dye — which turns purple when the cell is alive — to the product in question. A machine then measures how much dye remains, and that determines how many living cells are left. More living cells equals a less irritating product and a more satisfied consumer.