It has a reputation for being the entry-level grinder for entering the world of espresso. The Graef CM800 is frequently traded as an affordable starter model, but how good is it really? What can you expect for €130, and is it genuinely suitable for espresso beginners? We put the Graef through its paces in our lab—and after the first few hours, we were thoroughly frustrated! The coffee simply didn't taste good. But we didn't write it off; instead, we kept testing, tweaking, and modding to see if we could extract something decent from this grinder. Our two-year journey with the Graef is summarized in this review.
Why We Test the Way We Do—and Why We Test at All
Our goal is to introduce you to machines and practical workflow tips that help you achieve a fantastic coffee experience at home using accessible means and a limited budget. That's why we at Kaffeemacher run our own coffee farm, a roastery, cafés, and a coffee academy.
When we recommend a machine, it's because we are genuinely convinced by it and know you can craft great coffee with it. If specific workflow tips are needed to get a good result, we supply those right alongside our reviews.
We do not earn money from selling this grinder or from our tuning advice, allowing us to be completely honest with you!
First Impressions: Graef CM 800
Price and compact dimensions are the major selling points of the Graef. Measuring 13.5 cm in depth, 23 cm in width, and 39 cm in height, it fits easily into almost any kitchen. Weighing 2.6 kg, its build quality feels surprisingly solid for the price.
Another positive note: it can produce espresso-fine coffee grounds, unlike many other budget grinders under €200. Anyone who finds the right calibration for their beans can actually brew a real espresso.
| Specification | Graef CM800 |
|---|---|
| Price | approx. €130 |
| Dimensions (W × D × H) | 23 × 13.5 × 39 cm |
| Weight | 2.6 kg |
| Grind Adjustment | Steps 0–40, internal collar adjustment required for fine espresso |
| Dosing Control | On/Off switch, no timer functionality |
| Retention | approx. 8 g |
Our Verdict Upfront on the Graef CM 800
You can indeed grind fine enough for espresso. However, hitting the correct grind size is extremely difficult. Operating this grinder is far from straightforward. You'll even need to be comfortable using a screwdriver to unlock its full grinding range. In our opinion, the Graef is suitable for sensory beginners with advanced technical patience.
Grinding Fresh Espresso with the Graef CM800
Just 15 minutes after grinding, coffee grounds lose a massive portion of their volatile aromatics. This happens due to the vast increase in surface area and the rapid oxidation reaction with air. Pre-ground coffee is therefore always inferior to freshly ground coffee. Espresso grinders must grind significantly finer than general filter coffee grinders to build proper extraction resistance. If coffee grounds are too coarse, your espresso flows too quickly, resulting in under-extraction and a unpleasantly sour taste. The Graef can make a massive difference in taste compared to pre-ground coffee—a true quantum leap from pre-ground store coffee to freshly ground beans.
Can Something This Cheap Taste Good?
We spent countless hours with the Graef to master its finicky grind adjustment and pull a balanced espresso. To guarantee that our negative taste observations weren't caused by the espresso machine, we pulled shots on a commercial La Marzocco GS3—a machine priced like a small car.
Our espressos tasted bitter while simultaneously exhibiting an aggressive, harsh sourness. Despite sticking to our standard target brew ratio (18 g coffee to 45 g espresso output) and a textbook 25-second extraction time, the espresso tasted poor.
To evaluate our sensory impression objectively, we conducted a blind Triangle Test (triangulation). Three espresso cups were presented blind to a taster: two shots came from the exact same extraction, while one was the outlier. We asked the taster to identify the odd cup out and name the worst-tasting shot. Across 6 consecutive blind sets, the Graef CM800 shot was identified every single time as the worst-tasting espresso.
Particle Size Distribution as the Root Cause of Bad Espresso
During grinding, coffee beans are shattered into particles of varying sizes—some larger, some smaller. This is known as particle size distribution. The wider the variance in particle sizes, the harder it is to extract a balanced espresso. During brewing, large particles remain under-extracted while tiny fines over-extract. Instead of a harmonious cup, you get a harsh mixture of bitter and sour notes simultaneously. On the Graef, particle distribution is spread far too wide. Using laboratory sieves, we discovered that out of 50 grams of ground coffee, only 20 grams fell within the ideal size range. Roughly 10 grams were far too fine, and about 20 grams were far too coarse.
Lab sieve analysis of 50 g espresso grounds from the Graef CM800.
Grind Analysis via Laser Diffractometry
With the help of Benjamin Schütz, coffee expert and roaster, and the specialized firm Sympatec, we analyzed particle size distribution across multiple grinders using laser diffraction. We dialed in each grinder for a standard recipe (18 g coffee to 50 g liquid yield in 25 seconds). We tested: Anfim Practica as a commercial benchmark, Eureka Mignon Perfetto, Macap M2D, Sage Smart Grinder Pro, Baratza Sette 270Wi, and the Graef CM800.
The Graef CM800 exhibited the lowest, broadest primary peak. This means the grind size scatters widely without a uniform target particle size. Furthermore, the proportion of coarse boulders was significantly higher than on competing grinders.
Lowest Strength and Extraction Yield on the Graef CM800
Additionally, we measured beverage "strength" (TDS—Total Dissolved Solids) in the cup. The Graef lagged significantly behind competing grinders. It yielded only ~17.9% extraction yield in the cup, whereas competitor grinders reached up to 21.5%. Sensorially, this manifested as a watery, hollow-tasting espresso.
Grinder Test Re-Evaluation — Graef CM800 Under the Microscope Again
Follow-up testing in 2022 reconfirmed these initial lab findings. Repeat laboratory analysis showed a broad particle distribution curve and a significant coarse particle peak. Achieving a tight, precise particle spectrum remains physically difficult with this burr assembly.
Operation and Grind Size Adjustment on the Graef CM800
Grind size adjustment is the single most critical setting on any coffee grinder. It dictates how fine or coarse the grounds are, controlling liquid flow rate and extraction time.
The Graef features an outer adjustment dial numbered from 0 to 40. Unfortunately, out of the box, shots gushed through in just 12 seconds even on the finest setting (setting 0). It was still far too coarse. Therefore, we had to perform an internal mechanical adjustment on the burr carrier collar.
To do this, you must open the grinder housing and loosen two small screws on the upper burr carrier. This allows you to shift the internal collar indexing to move the entire range into an espresso-usable window. We demonstrate this step-by-step in our review video.
While this internal calibration is possible, it is extremely tedious and practically a dealbreaker. Beginners drawn in by the low price point will have their patience severely tested. There is a real risk that instead of welcoming newcomers to home espresso, it repels them through frustrating complexity.
Grinding is activated via an On/Off switch. You must weigh doses manually beforehand, as there is no timer function.
You can find suitable grinder cleaning tablets here in our shop.
Ground Coffee Retention
By retention, we mean hidden spaces inside the grinder chamber where stale coffee grounds get trapped. The higher the retention, the more stale grounds land in your portafilter basket during your next session. Total retention on the Graef measures roughly 8 grams. That is quite high!
Verdict: Is the Graef CM800 Worth It?
The biggest pro is that the Graef is one of the very few grinders in its price bracket capable of physically grinding fine enough for espresso. However, reaching the correct grind setting requires tedious internal disassembly and recalibration.
The particle size distribution is so broad that coffee grounds extract unevenly despite hitting target shot times. You end up with a mix of under-extracted sourness and over-extracted bitterness in the same cup.
Many beginners pair the Graef with a budget De'Longhi Dedica EC 685. While both machines allow you to brew a low-cost shot, whether that shot tastes pleasant remains questionable. For beginners especially, equipment needs to perform reliably so you can learn without fighting mechanical flaws. Therefore, we cannot truly recommend the Graef CM800. If you don't mind wasted coffee grounds and tweaking internal screws, you can give it a try—otherwise, look toward slightly higher-tier entry grinders.
