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On this interactive site you will experience the 75-year success story of DIATEST Hermann Költgen GmbH.
From the foundation as a one-man business in 1948 to today's worldwide operating company.
Let us start the journey.


Company foundation

At 1st April 1948, Mr. Hermann Költgen, a disabled person, and his wife Erna set up the company together.
Sub-supplier of the company BUKO in Ober-Ramstadt.
Company’s domicile: Darmstadt, Darmstraße 9, Starting capital: DM 1.000,-- borrowed from his mother.


Move to Martinstraße in Darmstadt with 2 employees


Now 15 employees.
Business relation with the company „Meßgeräte Bauer“ with trade name „Intast“.


Foreman’s qualifying examination by Hermann Költgen


Registered patented trade name DIATEST


Move to new building in Stiftstraße 50 in Darmstadt


Extension to Stiftstraße 48, Darmstadt with boss, boss’s wife and 20 employees.
At this time several utility patents and patent applications are made.


Company moves into first large new building at Schottener Weg 6, Darmstadt


25 years of DIATEST

Already working in the export with world-wide reputation


In February 1974 Erna Költgen dies.

In November 1974 marriage with Sigrid Költgen.
In this period the responsibility is more and more taken over by Mr. Peter Zander.
High qualification and business thinking are decisive for his appointment as CEO.
The company develops very positively with his assistance.


DIATEST Gauges & Tools Inc. is founded in Chicago / U.S.A.


DIATEST (U.K.) Ltd. is founded in London


The death of Hermann Költgen strongly hits the company.

In the same year his widow Sigrid Költgen founds Hermann Költgen GmbH. Sigrid Költgen – shareholder & CEO – gives the company a solid base together with the CEO Peter Zander.

The expansion of the company is preconditioned. Trusting co-operation with our business partners and the production of high-quality measuring instruments lead to success.


Daughter Gabriela joins the company on July 1st, after having successfully finished her training as a commercial employee


On January 1st, academically trained engineer Mr. Klaus Orio joins the company as export manager.

He together with Astrid Junghans and Mr. Gösta Fehle, former export agent, successfully build up the export department at the factory within 6 months which has now worked independently since the 1st July, 1988.


In spring the automatic lathes and production of blanks are moved to Ober-Ramstadt because of lack of space.

Most modern CNC-machines are bought.

In October the shareholder & CEO Sigrid Költgen dies.

Through direct line of succession her daughter Gabriela Orio becomes shareholder of DIATEST and manages the company together with her husband Klaus Orio as CEO.


DIATEST-France is set up


The in-house measuring room is equipped


DIATEST-Japan is set up.
The first trade relations with China are established.


The in-house CAD-facility is put into operation


DIATEST is certified according to DIN EN ISO 9001

The company is extended by the neighbouring estate. The automatic lathes are re-incorporated to Darmstadt.

An in-house waste plant is installed.


A new CNC-milling machine is supplied.
The administrative section is renovated inside and outside.
A new large training and show room is available.
All office working places are computerised and connected by an internal network.


After having put up the intranet, e-mail and internet are built up.
On May 10, the company gets a CNC-automatic lathe.

From May 14 to 17, DIATEST celebrates its 50th anniversary.
All representations are invited. Ceremony is on May 16, at Justus-Liebig-Haus, Darmstadt.

With pride an pleasure we look back at 50 years of DIATEST.

We continued the philosophy of our founder, Hermann Költgen. This is based upon quality, fast and punctual delivery times and fair partnership. These are the important targets for our company. Worth mentioning is, above all, the large personal involvement of our dealers for our products as well as our qualified employees who are guarantors for quality and reliable deliveries.

Our customers and our stuff members form together the big DIATEST-family. This feeling of partnership has guided us through ups and downs and made us become sucessful in the market. In the bore gauging sector we have reached a leading position on the world market. We look forward optimistically to the future having at the moment 70 employees and 43 country representations.

We are going to cultivate the idea of the big DIATEST-family and assure you of this partnership in the future.



Scandinavia is calling: Foundation of DIATEST Sverige AB in Bromma (Sweden)



DIATEST FRANCE S.A.R.L. becomes subsidiary company and moves to Paris

250,000 BMD plug gauges

After 25 years 250,000 DIATEST BMD plug gauges sold



For a better support of our customers in South America, DIATEST do BRASIL Ltda. was founded in Sao Paulo as headquarters

60th anniversary of the company

Son Florian Orio joins the company

After successfully completing his studies in mechanical engineering, Florian Orio joins the company

New booth concept

Due to the relocation of the leading CONTROL trade fair from Sinsheim to Stuttgart, a completely new booth was implemented


DIATEST Cup 2010

In the DIATEST Velodrom, national and international cycling champions as well as Olympic participants were in the starting field. DIATEST has been promoting youth sports of the Velociped-Clubs 1899 Darmstadt e.V. (VCD) for many years and supports them in maintaining the race track - the DIATEST Velodrom.

The TD-Gauge+ thread gauge is patented

Already 3 years later, in 2013, the digital version followed.
2019/2020 saw the launch of the motorized TD-Gauge+.

The DIATRON1000 comes onto the market

The complete measuring system for bore measurement with fourth decimal place is ergonomic and easy to operate


COME Métrologie S.A.R.L.

Acquisition of 50% shares in COME Métrologie S.A.R.L. in Bonson, France


Foundation of DIATEST Measuring Instruments (Beijing) Co. Ltd.

DIATEST Measuring Instruments (Beijing) Co. Ltd. is founded as a joint venture in Beijing, PRC

Foundation of DIATEST-Vertriebs-GmbH in Darmstadt

The DIATEST-Vertriebs-GmbH is founded in Darmstadt

The new building - first construction phase

DIATEST reaches its spatial limits.
An additional new building with larger production halls and a modern administration is planned.
Starting signal for the enlargement of the production hall 1 and construction of the new parking deck.


Expansion of the management board

Dipl.-Ing. Florian Orio is entered in the commercial register as a further as a further CEO

The new building - Second construction phase

Ground-breaking ceremony for 2nd construction phase - start of construction of the new production and office building in Darmstadt.
In front of our employees and numerous guests and dealers from Germany and abroad, the mayor of the city of Darmstadt and the president of the Chamber of Crafts honored the achievements of DIATEST in addition to CEO Dipl.-Ing. Klaus Orio. 


The new building complex

The new building with an additional 2,000 square meters of space for production and administration is in operation

Grand opening ceremony for the new building complex

Grand opening ceremony and workshops on the occasion of the completion of the new building complex


Automation through robots

Presentation of the automated and robot-supported measuring cell for high-precision tactile measurement in the process, including digital measurement data transmission and evaluation.
Unique in the world of bore measurement!

Foundation of the DIA-@cademy

Further education and training center for applied metrology

First "Open House" day (TdOT) at DIATEST

A new successful concept:
Lectures by top-class speakers from science, research and practice.
Exhibitors show the latest measuring technology in use.
Guests are allowed into production and are shown the application in practice using a sample workpiece.


70 years of DIATEST

70 years of DIATEST - Young / Dynamic / Innovative

Acquisition of COME METROLOGIE S.A.R.L.

DIATEST COME METROLOGIE S.A.R.L. starts its business operations in St.-Just St.-Rambert.
The company was born from a merger of DIATEST France and COME Métrologie.


New calibration room of the highest grade

Opening of the calibration room of quality classes 1 and 2 for quality assurance.
The latest measurement technology at the highest level is available here.

Nomination for the Hessian Export Award

DIATEST was nominated for the Hessian Export Award, one of the three most successful export-oriented companies in Hessen!



Foundation of DIATEST Schober GmbH

In order to be even closer to the customer, the companies DIATEST-Vertriebs-GmbH and Werner Schober Präzisions-Messgeräte were united

Virtual Open Day (TdOT)

First purely virtual "Open Day" (TdOT) at DIATEST, organised by the DIA-@cademy


The world's first DIATEST in-process measuring device - IPM

The DIATEST IPM (solution for dynamic in-process measurement for quality assurance) is ready for use and is used in various production processes

DIATEST goes Social Media

First DIATEST YouTube channel and company page on LinkedIn


We bid farewell to our Managing Director, Dipl.-Ing. Klaus Orio
1941 - 2022

DLC Black Diamond - the latest standard

DLC Black Diamond - After almost 40 years, our split-ball probes are no longer chrome-plated but coated with DLC (Diamond-Like-Carbon).

Investments in delivery capability

Due to worldwide supply difficulties caused by pandemics and other crises, DIATEST is investing large sums in its ability to supply:

New machines for a higher vertical range of manufacture
Increase of the material stock
Installation of its own hardening shop
In-house coating-line for DLC coating and calibration room

Environment and sustainability

Mitigating climate change and protecting the environment concern us all. That is why we are reducing emissions, cutting energy consumption and using natural resources responsibly.

Our measures for climate protection:

Thermal insulation of all buildings
LED lighting in all rooms
Installation of a combined heat and power plant
Collection and consumption of rainwater
Purchase of green electricity and green gas
We support the approach of a circular economy


Solar power for DIATEST

We produce electricity with the sun and save approx. 53 tonnes of CO2 per year.
The solar modules deliver up to 100 kW peak.


For 75 years, the family business DIATEST Hermann Költgen GmbH has stood for quality, delivery reliability and fair partnership.

Innovation was the driving force behind DIATEST and is still decisive for our success today. Customers who choose our products acquire 75 years of experience and know-how at the same time.

We will continue to strive to expand our global leadership position in the field of high-precision measuring instruments and complete metrological solutions.

This success is only possible together with our globally committed representatives, customers and qualified employees.

We will continue on our successful path and assure you of a fair and reliable partnership in the future.

On 1 April 2023: