When Eureka launches yet another "Mignon" espresso grinder, one's knee-jerk reaction might be: "Another one?" After all, more than a dozen models in the Mignon family share a very similar design language.
However, the Eureka Mignon Libra partially breaks the mold. It is the first Mignon featuring an integrated scale. Output is no longer time-controlled; instead, grinding stops automatically once the target weight is reached inside the portafilter. It’s brilliant—when it works.
In this review, you'll discover how accurately the Eureka Mignon Libra weighs and grinds, and how smoothly it fits into your workflow alongside your home espresso machine. We also share practical tips for an optimal setup and evaluate the grinder's strengths and weaknesses.
In the meantime, Eureka has launched another version of the Libra: the Eureka Libra 65 All Purpose. We have tested this model as well.
In Short – Key Takeaways on the Eureka Mignon Libra in 2 Minutes
The Eureka Mignon Libra is a good espresso grinder. It builds on the strengths of the Eureka Mignon series, combines them, and upgrades the experience with Grind-by-Weight technology.
- The Libra's integrated scale works well: It can be calibrated easily and delivers accurate doses.
- However, the grounds chute doesn't aim perfectly into the portafilter, causing stray coffee grounds to scatter around the base of the machine during grinding.
- This is a common issue with Eureka Mignon grinders, which owners usually prevent on other models by tapping the portafilter mid-grind.
- With the Libra, tapping the portafilter is impossible because it disrupts the scale and aborts the grinding cycle.
- A dosing funnel solves this issue, but one is not included in the box. With a dosing funnel, the grinder is a great choice; without one, it can be frustrating. Eureka now offers an official funnel (see announcement below).
- Compatible dosing funnels can be purchased from Barista Legends* or from Wiedemann via Stoll*.
- To tare and start grinding, our Eureka Libra required a portafilter weighing at least 175 grams. Lightweight portafilters or dosing cups may not trigger the scale properly.
- Continuous manual grinding without weight mode is not straightforward. It still requires at least 175 g of weight on the fork (activated via the double cup icon on the display). Other grinders, like the Sette 270 Wi, handle manual mode better.
- Some bottomless portafilters do not sit securely in the fork mount.
A Modified Eureka Specialità with an Integrated Scale
Strictly speaking, the Eureka Mignon Libra is a Eureka Mignon Specialità retrofitted with a scale.
A smart upgrade is the inclusion of the larger adjustment dial from the Eureka Mignon XL, which improves one of the Specialità's main drawbacks. Otherwise, the Libra remains a classic Specialità at heart.
55 mm flat steel burrs sit inside a square aluminum body. Measuring 12.4 cm wide, 43 cm high, and 19.2 cm deep, its footprint closely resembles the Mignon XL.
The Libra retains the solid performance of the Specialità: At 79.8 dB, it remains relatively quiet. Exchange retention is 2.4 grams. Grinding 20.2 grams in 10 seconds places it in the upper-middle speed tier for home espresso grinders. Temperature increases slightly across consecutive grinding cycles, but averages a reasonable 36.1 °C.
There is a bright spot regarding grind adjustment: The Libra features the larger adjustment dial from the XL, allowing for finer control. However, due to its small adjustment mechanism, it will never rank among the easiest grinders to dial in.
Most importantly: The espresso tastes just as good as a shot from a Eureka Mignon Specialità. Expect a round, body-forward espresso. The burr set performs best with medium to darker espresso roasts.
Where to Buy the Eureka Mignon Libra
The following specialty retailers stock the Eureka Libra and come highly recommended. All of them offer calibration services for machine offsets.
Note: The links above are affiliate links. Ordering through them costs you nothing extra, but earns us a small commission that directly supports our independent testing equipment.
An Accurate Scale with One Major Flaw
The scale on the Libra is very accurate. It can be calibrated easily and delivers consistent target weights. Minor variances from the target weight are usually related to offset calibration. Shot after shot, the grinder delivers the exact programmed weight into the portafilter.
Unfortunately, there is a catch: While the weight inside the basket is spot-on, a fraction of a gram scatters all over the countertop around the grinder. The grounds chute is misaligned relative to the basket, causing coffee to spray around the portafilter.
This is a known issue across the Eureka Mignon series, which owners usually manage by tapping the portafilter during timed grinding. However, tapping the portafilter on the Libra triggers the scale's error handling and halts the grinding process.
This feels unfinished and is the result of fitting a scale onto an existing chassis without fully redesigning the chute alignment. An adjustable chute would easily solve this across different portafilters.
A calibration weight is not included in the box (though even much more expensive commercial grinders like the Mahlkönig E65s GbW omit one as well).
A Dosing Funnel Solves the Issue
A dosing funnel resolves the mess completely, though one isn't supplied in the box. Even the official Swiss distributor pointed out this workaround. Using a funnel makes complete sense: portafilters equipped with a funnel dock easily into the fork and catch 100% of the grounds. With a funnel attached, coffee spraying is completely eliminated.
Adding a dosing funnel is an easy workaround for the Eureka Mignon Libra's design flaw.
Recommended Dosing Funnels:
Espresso Workflow with the Eureka Libra
A Grind-by-Weight grinder simplifies espresso preparation immensely. Espresso is a short, concentrated drink with a typical brew ratio of 1:1.5 to 1:3. A popular, balanced ratio enjoyed by many is 1:2.5.
For a double espresso, a dose of 15 grams is ground fine. At a 1:2.5 ratio, target yield in the cup is 2.5 times the dose, or 37.5 grams of liquid espresso.
Traditional timed grinders require dialing in both grind size and timer duration. Finding the right dose means grinding, weighing, adjusting the timer, and repeating—a process that wastes time and coffee beans.
Timer duration cannot be set independently of grind size, because changing the grind size changes the mass of coffee dispensed per second.
A Grind-by-Weight grinder eliminates manual weighing. Lock the portafilter into the fork, the scale tares automatically, and the grinder delivers the exact target weight.
Note: When adjusting grind size, always purge about 3 grams of coffee at the new setting to clear exchange retention from the chamber before pulling your test shot.
Read our complete guide on dialing in specialty espresso here.
Verdict on the Eureka Mignon Libra
Without a dosing funnel, the Eureka Mignon Libra feels unfinished. In core metrics, it performs on par with the Eureka Mignon Specialità—which means it grinds well.
However, usability and cleanliness are severely compromised out of the box due to coffee spraying around the portafilter.
Equipped with a dosing funnel, dosing accuracy is excellent and workflow becomes enjoyable. In this combination, the Eureka Mignon Libra is a great Grind-by-Weight grinder that makes home espresso preparation effortless.
The brew ratio is a critical factor in espresso quality. Instead of manually weighing every shot on a scale, home baristas can trust the grinder to handle dosing accurately.
With a dosing funnel attached, the Eureka Mignon Libra is an excellent home espresso grinder for espressos and lattes alike.
Helpful Links:
Watch our review video on YouTube.
In Switzerland, the Libra is available at Quimbaya and Kaffee-Erlebnis.
*Links marked with an asterisk are Amazon affiliate links. Purchasing through these links costs you nothing extra, but provides us with a small commission that supports our testing equipment. Thank you!
SPOILER ALERT: MIGNON LIBRA DOSING FUNNEL IS NOW AVAILABLE 😍😍😍
Dear coffee community and Kaffeemacher followers, in coordination with the Kaffeemacher team, we would like to add this short note regarding the optimal use of the Mignon Libra. Our R&D department has designed a dedicated dosing funnel specifically tailored for the Mignon Libra fork to ensure zero coffee waste, especially when grinding larger doses. We recommend using this accessory for:
- > 8 grams for single shots
- > 15 grams for double shots
- 20 – 22 grams for triple shots
You can purchase the dosing funnel bundled with the Mignon Libra or separately as an accessory. Check with your local retailer for availability.
Available in chrome in two sizes:
- 58.3 – 57 mm
- 54 – 53 mm
For complete details, please check out our official «How To Use» video guide.
Please note that the Mignon Libra comes factory-calibrated. If you ever notice minor deviations, you can easily recalibrate the scale yourself in a few simple steps. For further support, contact your dealer or reach out directly via EUREKA Contact. We are happy to help.
We thank Kaffeemacher for their thorough review and wish you all wonderful brewing!
The Eureka Team 😊
