World's Thinnest Credit Card-Sized Computer Breaks 1mm Barrier

Breaking: Ultra-Slim Computer Shrinks to 1 Millimeter

A groundbreaking single-board computer has achieved the impossible: fitting an ESP32-C3 processor, e-paper display, NFC reader, and a Li-Po battery into a package just 1mm thick—matching the dimensions of a standard credit card in all three axes.

"This is not just another thin board; it's a full credit card form factor computer that redefines the term 'credit card-sized,'" said lead developer Krauseler in an exclusive interview. The device uses a flexible PCB, ultra-thin battery, and a custom e-paper display to eliminate bulk.

Engineering Feat: Thinner Than a Coin

To achieve the 1mm profile, the team cut out the center of a real NFC card to house the electronics. The flexible printed circuit board, combined with the thinnest available battery and a flexible e-paper panel, allowed them to stay within the thickness limit.

"A standard display connector would have been too thick, so we had to hand-solder ultra-fine wires," Krauseler explained. The result is a device that looks and feels like a standard credit card but packs a fully functional computer.

Background: Past Attempts Fell Short

Previous credit card-sized computers existed only in two dimensions—length and width—but were several millimeters thick. This project is the first to achieve genuine three-dimensional credit card dimensions, including the critical 1mm height.

While other thin electronics have pushed boundaries, none before managed to fit a processor, memory, display, wireless connectivity, and battery into such a slim envelope. The ESP32-C3's low power consumption and integrated Wi-Fi/Bluetooth were key enablers.

What This Means: Ultra-Portable Computing Gets Real

The breakthrough opens doors for wearable devices, smart cards, and discreet embedded systems. With an NFC reader on board, the computer can interact with contactless payment terminals or act as a digital ID.

"Imagine a credit card that can show your balance, authenticate transactions, and even run custom apps—all without bulging your wallet," Krauseler added. The e-paper display ensures low power consumption and readability in bright light.

Technical Specifications

• Processor: ESP32-C3 (RISC-V, Wi-Fi/Bluetooth)
• Display: Ultra-thin flexible e-paper
• Connectivity: NFC reader for contactless interaction
• Power: Thinnest available Li-Po battery, rechargeable via USB
• Thickness: Exactly 1mm

Industry Reactions

"This is a milestone in miniaturization," commented electronics analyst Dr. Elena Voss. "We've grown accustomed to thin tablets, but a fully functioning computer at 1mm challenges manufacturing paradigms."

The project has already attracted attention from makers and commercial prototypes. Krauseler plans to open-source the design, allowing others to build on the concept.

Looking Ahead

While still a prototype, the credit card computer demonstrates that our pockets can hold far more than just plastic cards. Future iterations could integrate solar cells or biometric sensors.

Thanks to Joey for the tip that led to this report. For more details, see the background section above or contact the developer.