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Understanding Metric

Ready to Learn the Metric System? We are here to help!

Learning the SI (International System of Units, commonly known as the metric system) is easy. Begin with basics, including the 7 base units that define 22 derived units and using prefixes. Practice! Build proficiency and confidence making measurements using metric tools. Use reference points to develop an understanding of "how much." Estimation skills are key to sensemaking and checking for reasonableness of a measurement result. Learning metric is an interdisciplinary activity, so make connections to everyday life and career applications. You’ll find that writing with the SI is an effective way to communicate technical information. Take a NIST webinar or seminar to learn more! Explore professional development opportunities offered by the NIST Metric Program.

When you’re ready, explore the technical details NIST SP 330 and SP 811. Learn unit conversions between SI and non-SI units when necessary. Try the NIST Metric Trivia Quiz online or use the Alexa skill to test your knowledge and be on your way to thinking metric!

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Created May 11, 2016, Updated August 25, 2021