Scale Magazine Fall 2003
"Round Scale Roundup"

This "Roundup" comparison is between two digital mini scales that look similar but are extremely different.   These two scales are made by two totally different manufacturers with totally different specs and modes.

We have been asked many times "what are the differences between the Mini and the Micro?".  These scales are both round (which in itself is very strange for a scale) which makes them certainly have a resemblance - but that resemblance is not even skin deep.

So we thought it was time that we "Round up" these two round scales and have ourselves a little comparison test.

Jennings Mini





Weighing System U-Shaped Load Cell U-Shaped Load Cell
Stabilization Time ~1 Second ~1 Second
Maximum Capacity 150 Grams 120 Grams
Modes Grams, Ounces, Carats, Pennyweight (4 modes) Grams & Ounces (2 modes)

Tare Maximum

150 Grams

120 Grams

Recalibration Yes, with standard 100g weight No,  no user recalibration
Size 3" (78mm) 3⅛" (80mm)


2 Years

1 Year (5 years*)


Loose items tray,  Plastic case, 3 Lithium batteries

Loose items tray, Plastic case, 2 Lithium batteries


Shenzhen China

Shenzhen China

Suggested Retail



Mode MINI Micro-Tech
Grams 150g x 0.1g 120g x 0.1g
Ounces 5.300oz x 0.005oz 4.25oz x 0.01oz
Troy Ounce 4.820ozt x 0.005ozt  (no function)
Pennyweight 96.5dwt x 0.1dwt  (no function)

Testing Results:

We tested 5 Minis Vs 5 Micro-Techs.  All scales were put in a 70f room and allowed to sit for 24 hours before tested.   Our test facility is a controlled environment that allows us to fully evaluate scales.  First (if possible) we calibrate the scales using a 100gram F1 weight.  We use F1 test weights for all of our tests and record the results on a spreadsheet to fully compare the products.   Each scale is tested by placing a 0.5, 1, 2, 5, 10, 20, 50, 100 and 150 gram weight on the tray 10 times.   The results are then compared for an overall accuracy number, skew (reproducibility) and stability.    Then we put the scales into a 40f refrigerator for 30 minutes,  removed them and then ran the tests again in order to test for temperature compensation.

The Jennings Mini pulled ahead in most categories with better accuracy, better reproducibility and better resolution. This was not really a fair test however because the Mini is recalibratable and the Micro-Tech is not.  This means you can recalibrate the Mini with a 100g weight to make it perfectly accurate.  However the Micro-Tech is NOT recalibratable - so if your scale is inaccurate there is nothing you can do to make it read accurately.  In Ounce mode the MINI reads to 0.005oz whereas the MicroTech reads to 0.01oz.   We liked the Micro-Tech's LCD better then the MINI (it appeared clearer with bigger numbers).

The Micro-Tech consistently read incorrectly by 0.2g.   This is evidenced in the picture.   The Micro-Tech could not be calibrated so we had to accept that all of our Micro-Techs were off by 0.2g.

This was quite frustrating for us because we knew that if we could have recalibrated these Micro-Techs they would have worked much better. The Micro Tech is made by Bonso which has a reputation for building quality scales.

This led to a very lopsided competition where there Jennings Mini was always accurate +/- 0.1g and the Gram Precision Micro-Tech was accurate +/- 0.2g


We must say that we really do not like the round design of either of these two scales.  It's not very intuitive and it doesn't look very appealing to the eye.  That being said,  we felt the MINI was a better choice then the Micro-Tech.  The Mini has these winning characteristics:
a) User Recalibration (see below)*
b) The Mini reads to 0.05oz while the Micro-Tech only reads to 0.1oz
c) The Mini has a bigger 150g capacity compared to the Micro-Tech's 120g capacity
d) The Mini reads in 4 modes whereas the Micro-Tech reads in 2
e)  The Mini runs on 3 lithium batteries whereas the Micro-Tech only runs on 2.  This means the Mini will run 50% longer before needing new batteries.  This can be a big bonus in the field.
f) The Mini costs 35% less then the Micro-Tech! 
If you're in the market for a round scale, the Mini appears to be a significantly better value.  

Notes:  We are not preferential to the round design of these scales.  In real world use, it makes more sense (space-wise) to use a rectangular shaped scale.  The AXE which we recently reviewed shows a more intuitive design yet uses the same safety and design premise as these round scales.

*Here is a typical question that we receive (quote from an email): hello, i have a Micro-Tech pocket scale and I am having some problems with it.  It doesn't weigh what it is suppose to - like a Loonie weighs 5grams instead of 7g. I don't know what is wrong,  I've changed the batteries and still the same. If you have any information you could give me on why it's doing this please let me know! thank you! (Mike Coombe, Ontario Canada)
Unfortunately since the Micro-Tech is not recalibratable, there is no viable solution to his problem.

Additional Round Scales:

There are yet more similar round scales that we did not test in this competition.  These additional round scales are marketed by the companies KERN and Pesola.  Although these scales are sold in North America as well, they are not as popular as the MINI or the MICRO and their specs are the same as the Micro Tech (120g x 0.1 and not recalibratable).  Therefore we did not bother entering them in this competition.

Learn More about these Scale Companies:

WARNING: ITIN Scale Co has imported a copy of the Gram Precision Micro Tech!  It's called the "Minx Mini Disc".  The Itin knockoff is NOT MADE BY BONSO OR JENNINGS.  It's just a low quality knockoff and should be avoided!


We encourage you to provide feedback on this article and/or tell us your personal experience with a scale.

Important Disclaimer:   Scales are sometimes difficult to compare.  Our results are just a sample of tests done at random conditions.  The actual operating conditions of your scale may vary from our test conditions and your results may differ from our results.   We did our best to test the scales in a blind and unbiased manner.  We receive money and other consideration from companies that advertise on, and support this site.  We do our best to not allow this to affect the results of our tests and evaluations.  However, we strongly recommend that you do your own comparison tests in your actual operating environment to determine which scale is best for your needs.    The terms Jennings, Mini, Gram Precision, Bonso, Micro-Tech are trademarks of their respective parties.  Names are used for comparison purposes only and for the purposes of this article.  No other rights are expressed or implied.  This article and all images therein are copyright 2003 

2003, 2004 All Rights Reserved