Close

What's a Thermochron?

A project log for ChillPoint — Handheld Thermochron Temperature Mgr

chillPoint — handheld Wi-Fi reader for iButton temperature loggers

geoffrey-wellsGeoffrey Wells 07/02/2026 at 13:440 Comments

What Is a Thermochron iButton?

One of the questions I get most often is, "What exactly is a Thermochron iButton?"

If you've never seen one before, you're not alone. Despite being used around the world for temperature monitoring, they're still relatively unknown outside of industries that rely on them.

A Thermochron iButton is essentially a self-contained temperature data logger packaged inside a rugged stainless-steel can about the size of a coin (roughly 17 mm in diameter). Inside that tiny enclosure is:

Once programmed, the iButton wakes itself up at user-defined intervals—anywhere from once a minute to every few hours—records the temperature, stores the reading internally, and then goes back to sleep to conserve battery power. Depending on the model, it can store thousands of temperature samples and operate unattended for months or even years.

Why are they so popular?

The biggest advantages are their simplicity and durability.

Unlike many modern data loggers, a Thermochron doesn't need Bluetooth, Wi-Fi, cellular service, or even a display. You simply configure it, place it where you want to monitor temperature, let it collect data, and retrieve the results later.

Because they're sealed in stainless steel, they're resistant to dirt, moisture, vibration, and rough handling, making them ideal for demanding environments.

Common applications

You'll find Thermochrons being used for:

Anywhere someone needs to know what the temperature was over time, a Thermochron is a good candidate.

Why I built ChillPoint

Although the iButtons themselves are incredibly capable, the tools for configuring and reading them have traditionally required a Windows PC and a specialized USB adapter. That's fine in a lab, but it's not very convenient when you're in the field.

The goal of ChillPoint is to make working with Thermochrons much easier by providing a completely handheld, battery-powered device that can configure iButtons, download their logged data, and review temperature records without needing a laptop.

Please consider subscribing to my campaign: https://www.crowdsupply.com/g9six/chillpoint

Discussions