The Complete Guide to Anthropometric Instruments

Anthropometric instruments are precision tools used to measure the dimensions of the human body. From height and limb length to skinfold thickness and bone width, these measurements are essential in fields ranging from clinical nutrition and sports science to forensic anthropology and military fitness assessment.

This guide covers every major category of anthropometric instrument, explains what each tool measures and who uses it, and helps you determine which instruments you need for your specific application.

What Is Anthropometry?

Anthropometry is the systematic measurement of the human body and its parts. The term comes from the Greek "anthropos" (human) and "metron" (measure). Anthropometric data is used to assess growth, nutritional status, body composition, and physical characteristics across populations and individuals.

Anthropometric measurements fall into several categories: linear dimensions (heights, lengths, and breadths), circumferences, skinfold thicknesses, and skeletal dimensions. Each category requires specific instruments designed to deliver repeatable, accurate results.

The two most respected manufacturers of anthropometric instruments in the world are GPM Instruments (Gneupel Projects & Mechatronics) based in Switzerland and Holtain Ltd based in Wales. Seritex is the exclusive authorized North American importer and distributor of both brands and has been since 1986.

Anthropometers

An anthropometer is the most versatile instrument in anthropometry. It consists of interconnecting graduated metal rods that can be configured to measure nearly any linear dimension of the human body, including standing height, sitting height, limb lengths, and segmental dimensions.

The rods are engraved with millimeter graduations and connected end to end to form a measurement beam. A sliding branch holder moves along the beam, and the operator reads the measurement through a scale window on the holder. When only the upper sections are used with opposing measurement branches, the anthropometer doubles as a large sliding caliper for breadth measurements.

GPM Anthropometer (Model 100) — The gold standard, also known as the Martin anthropometer after its inventor Rudolf Martin. Measuring range of 0 to 2,100 mm. The four interconnecting tubes feature reinforced ABS expanding mandrels produced with 3D printing technology. Accessories include recurved measuring branches (Model 102), a carbon fiber baseplate (Model 1013), and an auricular height needle (Model 103).

Holtain Harpenden Anthropometer (Model 601) — The British counterpart to the GPM, developed as part of the Harpenden Growth Study. Uses a similar beam-and-branch design with Holtain's precision counter mechanism for readings.

Who uses anthropometers: University researchers in kinesiology, physical anthropology, and ergonomics; military body composition assessment programs; growth monitoring studies; forensic anthropologists; and anyone conducting full anthropometric profiles per ISAK (International Society for the Advancement of Kinanthropometry) protocols.

Which do I need? For most research and clinical applications, the GPM Anthropometer (Model 100) or the Holtain Harpenden Anthropometer (Model 601) will serve. If you need to measure heights from a standing position, add the baseplate accessory. If your work involves segmental thorax measurements, add the recurved measuring branches.

Stadiometers

A stadiometer is a vertical ruler with a sliding horizontal headboard used to measure standing height. Stadiometers are among the most commonly used anthropometric instruments in clinical settings and are standard equipment in pediatric offices, research labs, sports medicine clinics, and military processing centers.

Precision stadiometers differ from the height rods found on clinic scales. Research-grade instruments like the Harpenden stadiometer use a counter mechanism or digital readout to deliver measurements accurate to 0.1 mm, compared to the 1 mm (at best) resolution of standard clinical height rods.

Holtain Harpenden Wall Mounted Stadiometer (Model 602VR) — The most widely cited stadiometer in research literature. Mounts permanently to a wall and uses Holtain's high-speed counter mechanism for precise readings. Range of 600 to 2,100 mm.

Holtain Harpenden Portable Stadiometer (Model 603VR) — The same precision as the wall-mounted version but designed for field research. Breaks down for transport and can be set up in any location with a flat floor and a vertical surface.

Holtain Sitting Height Table (Model 607VR) — Measures sitting height (vertex to seated surface), which is used to calculate leg length and the sitting height ratio — an important indicator in growth assessment and body proportionality studies.

Holtain Pocket Stadiometer (Model 608) — A compact, portable option for field measurements where full-size stadiometers are impractical.

Who uses stadiometers: Clinical dietitians, pediatricians, endocrinologists monitoring growth disorders, sports scientists tracking athlete development, military intake processing, epidemiological surveys, and any study requiring standardized height measurement.

Skinfold Calipers

Skinfold calipers measure the thickness of a fold of skin and the underlying subcutaneous fat at specific body sites. Skinfold measurements are one of the most practical and widely used methods of estimating body fat percentage and are central to body composition assessment protocols including those used by the ISAK and the U.S. military.

A skinfold caliper applies a standardized pressure (typically 10 g/mm²) to the skinfold through spring-loaded jaws. The operator pinches a fold of skin, applies the caliper, and reads the measurement from a dial gauge or digital readout. Accuracy depends on both the instrument's calibration and the technician's skill.

Holtain Tanner/Whitehouse Skinfold Caliper (Model 610ND) — Developed by James Tanner and R.H. Whitehouse at the Institute of Child Health in London. This caliper maintains constant jaw pressure across its full range and features the distinctive yellow dial gauge. It is the reference caliper for many published body composition equations and is required by several certification programs.

Who uses skinfold calipers: Clinical dietitians assessing patient body composition, sports nutritionists working with athletes, military body composition assessment programs (the U.S. Army, Navy, and Marine Corps all use skinfold protocols), personal trainers, ISAK-certified anthropometrists, and researchers conducting population health surveys.

Sliding Calipers

Sliding calipers (also called beam calipers) measure linear distances between two points using a graduated beam with one fixed and one sliding jaw. In anthropometry, they are primarily used for breadth measurements of the trunk, shoulders, and pelvis — dimensions too large for spreading calipers but requiring more precision than a tape measure.

The sliding caliper works on the same principle as the upper section of an anthropometer used in caliper mode, but as a dedicated single-purpose instrument it is lighter and easier to handle for repeated measurements.

GPM Sliding Caliper, Martin type (Model 104) — The standard sliding caliper for anthropometric use. Range of 0 to 200 mm with millimeter graduations. Used for small to medium breadth measurements.

GPM Sliding Caliper with Vernier (Model 105) — Same design as the Model 104 but with a vernier scale for readings to 0.1 mm precision. Used when maximum accuracy is required.

GPM Sliding Caliper, Poech type (Model 114) — A larger sliding caliper designed for measurements up to 300 mm, with an angular scale for measuring facial angles in addition to linear dimensions.

Holtain Bicondylar Caliper (Model 604) — Specifically designed for measuring the breadth of bony condyles (knee, elbow, wrist, ankle). These measurements are used in body composition equations and frame size assessments.

Who uses sliding calipers: Researchers conducting ISAK anthropometric profiles, physical anthropologists, ergonomic designers measuring body dimensions for product design, and clinicians assessing frame size as part of nutritional evaluation.

Spreading Calipers

Spreading calipers measure the distance between two points using curved arms that spread apart from a central pivot. Unlike sliding calipers that measure in a straight line along a beam, spreading calipers measure the direct distance between two anatomical landmarks — even when the surface between them is curved.

They are essential for craniometric measurements (head and skull dimensions) and for measuring dimensions of the trunk where the body's curvature makes a straight-line caliper impractical.

GPM Small Spreading Caliper with Rounded Ends (Model 106) — Range of 0 to 300 mm. The rounded ends are used for measurements on living subjects where pointed tips would be uncomfortable.

GPM Small Spreading Caliper with Pointed Ends (Model 107) — Same range as the Model 106 but with pointed ends for precise landmark identification on skeletal material.

GPM Large Spreading Caliper with Rounded Ends (Model 108) — Range of 0 to 600 mm. Used for larger dimensions such as maximum head length and head breadth on living subjects.

GPM Large Spreading Caliper with Pointed Ends (Model 109) — Range of 0 to 600 mm with pointed ends for osteometric work.

Who uses spreading calipers: Physical anthropologists measuring cranial and postcranial skeletal material, forensic anthropologists, craniofacial researchers, and anyone conducting head measurements per standard anthropometric protocols.

Anthropometric Kits

An anthropometric kit bundles the instruments needed for a complete anthropometric assessment into a single carrying case. Kits reduce the cost of purchasing instruments individually and ensure the practitioner has a matched, calibrated set of tools.

GPM Small Instrument Kit (Model 112) — Contains the essential instruments for field anthropometry in a compact carrying case. Suitable for ISAK Level 1 assessments.

GPM Large Instrument Kit (Model 113) — A comprehensive set including the anthropometer, sliding caliper, spreading caliper, and accessories. Suitable for ISAK Level 2 and Level 3 assessments.

GPM Poech Large Instrument Kit (Model 113PC) — Includes the Poech-type sliding caliper and additional instruments for a more complete range of measurements.

GPM Complete Large Instrument Kit (Model 113C) — The most comprehensive kit available, containing the full range of GPM instruments needed for any anthropometric protocol.

Who uses anthropometric kits: University departments equipping teaching labs, researchers outfitting field studies, sports institutes building body composition assessment programs, and military units establishing fitness evaluation stations.

Choosing a kit: For ISAK Level 1 certification, a small kit with a skinfold caliper, bone caliper, and tape measure is sufficient. For ISAK Level 2 and above, or for comprehensive research protocols, the large kits provide the anthropometer, multiple calipers, and accessories needed for the full measurement battery.

Infantometers and Neonatal Measuring Instruments

Infantometers measure the recumbent length of infants and young children who cannot stand for a standard height measurement. Accurate length measurement in infants is critical for growth monitoring, nutritional assessment, and identifying growth disorders.

Holtain Harpenden Infantometer (Model 702) — A precision measuring board for infants up to approximately 920 mm in length. Features a fixed headboard and sliding footboard with Holtain's counter mechanism.

Holtain Harpenden Infantometer XL (Model 702XL) — Extended version for measuring older children in the recumbent position, with a range up to approximately 1,100 mm.

Holtain Harpenden Neonatometer (Model 701) — Designed specifically for neonates, with a smaller frame and finer graduations appropriate for very small subjects.

Holtain Harpenden Infant Measuring Table (Model 705) — A complete measuring station for infant anthropometry.

Who uses infantometers: Pediatricians, neonatal intensive care units, pediatric dietitians, public health programs monitoring child growth (e.g., WHO growth standard assessments), and researchers studying early childhood development.

Craniometric and Osteometric Instruments

GPM manufactures a specialized range of instruments for the measurement of skulls, bones, and craniofacial structures. These instruments are used primarily in physical anthropology, forensic anthropology, and archaeological research.

GPM Osteometric Table (Model 217) — A flat measuring surface with a fixed vertical endboard and a sliding vertical board for measuring the maximum length of long bones.

GPM Mandibulometer (Model 218) — Measures dimensions of the mandible (jawbone) for forensic and anthropological analysis.

GPM Cubic Craniophor (Model 201) — A device for holding and orienting a skull in a standardized position (the Frankfurt Horizontal Plane) for consistent measurement.

GPM Diagraph (Model 202) — Traces the contour of the skull in profile, producing a scaled drawing of the cranial outline.

GPM Coordinate Caliper (Model 115) — Measures both the depth and height of a point simultaneously, useful for three-dimensional cranial measurements.

GPM Goniometer (Model 117) — Measures angles between anatomical planes and landmarks.

Who uses these instruments: Forensic anthropologists identifying skeletal remains, physical anthropologists studying population variation, bioarchaeologists analyzing skeletal collections, and museums curating osteological collections.

Accessories and Replacement Parts

Maintaining the accuracy of anthropometric instruments requires periodic calibration, proper storage, and timely replacement of wear components.

GPM Caliper Checking Gauge (Model 219) — A precision gauge for verifying the accuracy of calipers. Essential for any lab or program that needs to document instrument calibration.

Holtain Calibration Rod (Model 602CR) — For verifying stadiometer accuracy against a known standard.

Holtain Replacement Counters — The mechanical counter on Holtain stadiometers and infantometers is a wear component. Replacement counters are available for the 600 series (stadiometers) and 700 series (infantometers/neonatometers).

Holtain Gear Sets, Headboards, Heel Plates, and Balance Weights — Individual replacement parts for Harpenden stadiometers, allowing field service without returning the instrument to the factory.

Choosing the Right Instruments for Your Application

Different fields and protocols require different combinations of instruments. Here is a guide based on common use cases:

ISAK Level 1 Certification: Skinfold caliper, small bone caliper (bicondylar), anthropometric tape measure. The Holtain Tanner/Whitehouse Skinfold Caliper and Holtain Bicondylar Caliper cover the caliper requirements.

ISAK Level 2 and Level 3 Certification: Everything in Level 1, plus an anthropometer, large sliding caliper, and segmometer. The GPM Large Instrument Kit (Model 113) or Complete Kit (Model 113C) covers these requirements.

Military Body Composition Assessment: Depends on service branch. U.S. Army and Marine Corps programs use skinfold calipers at multiple sites. U.S. Navy uses circumference measurements. A skinfold caliper (Holtain 610ND) and a stadiometer (Holtain 602VR or 603VR) cover most military protocols.

University Kinesiology Lab Setup: An anthropometer, stadiometer, skinfold caliper, spreading calipers (small and large), sliding caliper, bicondylar caliper, and calibration tools. The GPM Complete Large Instrument Kit plus a Holtain stadiometer and skinfold caliper provides a comprehensive teaching and research setup.

Clinical Nutrition Practice: A stadiometer for height, a skinfold caliper for body composition, and a bicondylar caliper for frame size assessment. The Holtain Harpenden Wall Mounted Stadiometer, Tanner/Whitehouse Skinfold Caliper, and Bicondylar Caliper are the standard clinical set.

Pediatric Growth Monitoring: An infantometer or neonatometer for recumbent length, a stadiometer for standing height (older children), and a calibration rod. The Holtain Harpenden Infantometer and Wall Mounted Stadiometer cover infants through adulthood.

Forensic and Physical Anthropology: An osteometric table, spreading calipers (pointed ends), sliding calipers, a craniophor, and a mandibulometer. GPM's craniometric instrument range is the standard for skeletal analysis.

Sports Science and Performance: An anthropometer for limb lengths and body proportions, a stadiometer for height, a skinfold caliper for body fat, a bicondylar caliper for frame size, and a sitting height table for proportionality assessment. A combination of GPM and Holtain instruments provides the full battery used by elite sports programs worldwide.

Why Instrument Quality Matters

Anthropometric measurements are only as reliable as the instruments used to take them. Research-grade instruments from GPM and Holtain are manufactured to tolerances that consumer-grade alternatives cannot match. This matters for several reasons:

Published body composition equations — the formulas that convert raw measurements into estimates of body fat, lean mass, and other metrics — were developed and validated using specific instruments. The Holtain Tanner/Whitehouse Skinfold Caliper, for example, is the reference instrument for many of the most commonly used skinfold equations. Using a different caliper with different jaw pressure characteristics can produce systematically different readings, introducing error into the results.

Longitudinal studies that track changes over time require instruments with exceptional repeatability. A stadiometer that reads 0.3 mm differently each time it's used will mask real changes in height — changes that may be clinically significant in growth monitoring or spinal health assessment.

Certification programs like ISAK require candidates to demonstrate measurement precision within specific technical error of measurement (TEM) thresholds. Instruments with poor manufacturing tolerances make it harder to achieve these standards.

About Seritex

Seritex has been the exclusive authorized North American importer and distributor of GPM and Holtain anthropometric instruments since 1986. Every instrument sold through Seritex is sourced directly from the manufacturer, carries a full factory warranty, and is backed by specialist technical support.

We serve university research labs, hospitals, military fitness programs, forensic anthropology departments, and individual practitioners across the United States and Canada. We accept purchase orders from institutions, offer NET30 terms for approved accounts, and provide expert guidance on instrument selection.

To discuss your instrument needs, request a quote, or place an order, contact us at info@seritex.com or call +1 (201) 755 4213.