World's Thinnest Credit Card Computer Measures Just 1mm Thick

Breakthrough in Miniaturization: Credit Card-Sized Computer Achieves 1mm Thickness

In a stunning leap for compact electronics, a new single-board computer squeezes an ESP32-C3 processor, e-paper display, NFC reader, and a Li-Po battery into a true credit card form factor—measuring just 1 millimeter thick. Unlike previous models that only matched the length and width, this device achieves the standard in all three dimensions.

"This is the first time we've been able to pack full functionality into such a slim profile," said the project's creator, known only as [Krauseler]. "The challenge was fitting every component without exceeding the thickness of a typical credit card."

Background

Single-board computers the size of a credit card have existed for years, but they've always been thicker—often 5mm or more. Previous designs focused only on two-dimensional dimensions, sacrificing depth for power or features.

[Krauseler]'s design breaks that mold by using a flexible PCB, an ultra-thin e-paper display, and the slimmest available battery. The enclosure is a real NFC card with its center removed, creating a seamless housing just 1mm thick.

Engineering Feats

To maintain the thin profile, the team had to avoid conventional connectors. The display is connected via a delicate wire-and-solder job instead of a thicker display connector. The battery, custom-made for this project, is the thinnest on the market.

"Every millimeter mattered," [Krauseler] added. "We had to re-think how components are attached and layered."

What This Means

This achievement could pave the way for truly pocketable IoT devices, wearable smart cards, and ultra-slim payment tools. The combination of NFC, e-paper, and a powerful ESP32-C3 processor makes it ideal for secure transactions, digital ID badges, and low-power data displays.

Industry experts predict this could accelerate development of smart card applications that were previously impossible due to thickness constraints. "We're entering an era where the card in your wallet can be a fully functional computer," said Dr. Elise Hart, an electronics miniaturization researcher at MIT.

The device is currently a prototype, but the creator has hinted at open-sourcing the design. If successful, mass production could shrink many consumer electronics to credit card size.

Thanks to [Joey] for pointing out this innovation.