Accredited laboratory by ATS



Metrology laboratory May 21st is accredited for calibration in the field of dimensional metrology

Length standards and measuring instruments
  • Line scales (steel and glass);
  • Ring and plug gauges;
  • Gauge blocks;
  • External micrometers;
  • Internal 2-point micrometers;
  • Internal 3-point micrometers;
  • Setting rods;
  • Calipers, depth gauges, height gauges;
  • Dial indicators;
  • Bore gauges;
  • Measuring tapes;
  • Measuring microscope;
  • Microscope standards;
  • 3D measuring instruments;
  • 2D measuring instruments;
  • 1D measuring instruments;
  • Thickness gauges and measuring instruments;
  • Gauges GO/NO GO;
  • Thread plug gauges;
  • Vee blocks;
  • Calibration blocks;
  • Measuring instruments of the railway program;
  • Linear transducers;
  • Form measuring instruments and roundness standard.
Angle measuring instruments
  • Bevels, protactors;
  • Squareness;
  • Spirit levels;
  • Angle encoders.
Roughness standards and measuring instruments
  • Roughness measuring instruments;
  • Roughness standards.
Flatness standards and measuring instruments
  • Surface plates;
  • Parallel and flatness glasses.
Force measuring instruments
  • Torque wrenches
Calibration requests

Please, take a calibration request form and filled up deliver by  e-mail or contact us via  contact form.

Calibration request

Certificate and scope of calibration

Why May 21st

ML May 21st takes care of its customers. We are aware of the importance of accurate measurement, which reflects on the quality of your products and according to this we apply modern methods of calibrating your measuring equipment.
Our team of experts is highly educated and professionally qualified for the services we provide.
Quality of calibration, validity of results and customer satisfaction are our main goals.

Continuous improvement of the quality of services we provide, while respecting standards and applying good laboratory practice. We are dedicated to customer satisfaction, as well as our personnel, with continuous improvement of management system and laboratory activities, training of personnel and investment in high quality calibration equipment.

To become number one in dimensional metrology calibration.


About us

Metrology Laboratory May 21st, Belgrade is an accredited calibration laboratory (ATS 02-052) in the field of dimensional metrology (length, angle, roughness, flatness, etc.). It was founded in 2011 and has been operating successfully ever since.

Fulfillment of the customer requirements, standards and good laboratory practice, competent personnel, as well as highest quality equipment, makes ML May 21st one of the leading calibration laboratories in the field of dimensional metrology.

Laboratory management and professional team are committed to impartiality and continuous improvment of the quality of services. Quality of service and customers trust is the primary goal and objective of all of us.

We perform calibration in the Laboratory and On-site, respecting the agreed deadlines.



How to reach us?

Metrology laboratory May 21st

Oslobođenja 1, 11090 Belgrade
+381 11 356 44 66
+381 64 647 01 86

If you would like to receive a calibration offer, you can leave your specification of measuring equipment and company information in the contact form, and we will contact you as soon as possible.