A connected hydrometer floats in your fermenter and sends gravity and temperature to your phone every few minutes. No more opening the fermenter to take samples: you watch the fermentation happen. Here's how the three most common ones work and how to choose.
A community project: a small Wi-Fi board, a motion sensor, a temperature probe and a battery sealed in a plastic tube. It floats at an angle that changes as the beer thins out; once calibrated, that angle gives the gravity. Parts cost around €30–40, or you can buy one ready-made from community sellers.
Alternative firmware for iSpindel hardware, with a friendlier web setup, more sending options and newer boards. Same principle, same calibration, same tube.
A ready-made, colour-coded hydrometer. It speaks Bluetooth only, so it needs a phone or a small gateway such as TiltBridge or TiltPi to reach the internet. Several colours let you follow several fermenters.
Typically within a few gravity points of a glass hydrometer, and very reliable for the trend. Take a hydrometer reading at the start and end, and let the sensor tell you what happens in between.
iSpindel and GravityMon run for weeks on a battery and need Wi-Fi at the fermenter. Tilt batteries last months, but the gateway must be within Bluetooth range.
We're preparing a build-it-yourself sensor and a cheap Tilt gateway. Until then, every sensor below works with Mashwerk today.
| iSpindel / GravityMon | Tilt | |
|---|---|---|
| Price | Low (DIY parts) | Higher (ready-made) |
| Setup | Build or buy, then calibrate | Drop it in, add a gateway |
| Connection | Wi-Fi, sends directly | Bluetooth, through TiltBridge, TiltPi or a phone |
| Several fermenters | One device per fermenter | One colour per fermenter, one gateway |
| Works with Mashwerk | Yes | Yes |
Pick iSpindel or GravityMon if you like tinkering or want the cheapest option; pick Tilt if you want something ready to use.
Keep one for calibration and for the first and last readings. The connected sensor tracks everything in between.
Sanitise it like any other equipment before it goes into the fermenter. Both iSpindel tubes and Tilts are sealed.
Yes, as long as the device fits through the opening and the Wi-Fi or Bluetooth signal gets out of the vessel.
It plots them next to your recipe's planned gravities, computes attenuation and ABV live, and the copilot can tell you when a fermentation stalls.
Free plan with one sensor and 90 days of readings, no credit card.
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