For Food, Beverage, Chemical, Petroleum, and Pharmaceutical Labs

Select a Refractometer for your demanding Laboratory application from the wide range of instruments available from Rudolph Research. Rudolph is a leading analytical laboratory instrument supplier, manufacturing precision quality benchtop instruments for the Pharmaceutical, Chemical, Petroleum, Petro-Chemical, Food, and Beverage industries.

All Rudolph instruments are designed to meet specific application requirements of specific industries and all are designed to exceed your requirements. A range of models and numerous configurations are available.

Refractometers From Rudolph Research Feature:

  • Easy-to-clean, shallow sample well – a clean sample well is imperative to accurate measurements
  • Durable sapphire prisms with long-life light sources – low life-of-instrument cost
  • Decades of leading analytical instrument design

High-Durability Sapphire Prism

All Rudolph Research J-Series instrument offer a sapphire prism for high mechanical and chemical durability. The sample well is acid resistant 316 stainless steel with a Techtron sealing ring. There is no lamp to change, the LED light source is guaranteed for 1,000,000 measurements.

Shallow Refractometer Sample Well – All Rudolph J-Series Models

Refractometer measurement accuracy is only as reliable as the cleanliness of the sample well. Hard-to-clean sample wells can lead to inaccuracies due to residual from a prior measurement. Rudolph Research set out to dramatically minimize this problem by taking a new approach to sample well design. The Rudolph sample well is very shallow and smooth allowing easier cleaning and less surface area for contaminants to hide. Less sample is required and the well cleans easily. The result is more accurate measurements due to significantly less opportunity for sample contamination.

Refractometer – Sample Temperature Control

Rudolph’s uniquely designed refractometer sample well and electronic heating and cooling system improves results. For many applications sample temperatures must be accurately controlled within the sample well. When an application requires highly controlled temperature, a temperature-controlled presser will assure even and highly accurate temperature stability. A sample in the measurement well that is controlled from both the top and bottom affords the most accurate measurement at a required temperature.

Refractometer - Sample Well

Refractometer - Sample Well Cross Section

Refractometer Models – 10 Models With Dozens Of Application-Specific Options

Rudolph understands your measurement applications and provides the needed instruments and configurations to meet your requirements. Application requirements may be dictated by regulatory agencies, quality control demands, or sample handling concerns. Refractometers may also be utilized in conjunction with other instruments for multiple measurements – load one sample to receive multiple measurement results. Sample delivery may also automated with or without other instruments for a complete laboratory automation solution designed to increase efficiency in your laboratory.

Laboratory Refractometer J457
The most advanced model, for very demanding pharmaceutical, analytical, and chemical labs

J457 Refractometer

  • Smart Measure™ improves results with live measurement and sample load well monitoring
  • Dual electronic temperature control – range 10ºC – 110ºC or 10ºC – 120ºC (optional)
  • Accuracy: refractive index ±0.00002, BRIX ±0.01
  • Widest measurement range: refractive index 1.26 – 1.72, BRIX 0 – 100
  • Data storage – 32GB non-removable compact flash – or fully networkable
  • Fully 21 CFR Part 11 compliance and on-board data storage

Refractometer J457 NDR
Hospital refractometer ideal for drug dispensing pharmacies

  • Ideal for hospitals in tracking narcotics and drug diversion
  • Store pre- and post- operating room sample measurements in a database
  • Secure login
  • Secure data backup

Refractometer J357
Excellent for pharmaceutical, chemical, petroleum, essential oils, fragrance, cosmetic laboratories

Laboratory Refractometer - J357

  • Dual electronic temperature control – range 15ºC – 100ºC or 10ºC – 120ºC (optional)
  • Accuracy: ±0.00004 RI, ±0.03 BRIX
  • High-durability sapphire prism
  • Data storage: removable media card or upload via RS 232 to LIMS systems

Wide Range Refractometer J257
High accuracy; wide range for polymer, petroleum, chemical, pharmaceutical, essential oil laboratories

Laboratory Refractometer J257

  • Wide refractive index range of 1.26-1.72 measures beyond instruments with only a food refractive index range of 1.33-1.53
  • Measures aromatic essential oils, fluorocarbon solvents, and all known materials
  • Large, easy-to-read, 7.5cm × 10cm cold cathode fluorescent back lit, digital LCD screen

Digital Refractometers J157 and J157-633
High accuracy for food, beverage, water based chemicals, & sugar industries

Refractometer J157

  • Measures to ±0.00002 RI / ±0.01 BRIX making it more accurate and reproducible than 4-decimal-place-wide range chemical refractometers
  • Dual electronic temperature control from the top and bottom of the sample well
  • Large range of standard and customized scales are available
  • Large, easy-to-read, 7.5cm × 10cm cold cathode fluorescent back-lit, digital LCD screen
  • J157-633 operates at 633nm for OWLS system bio-technical and bio-engineering labs

Refractometer J57HA, J57WR, J57TPN
Heavy use, high accuracy, QC


  • Wide measurement range for the chemical industry
  • High accuracy
  • J57WR offers an wide refractive index (RI) measurement range from 1.26 – 1.70

Refractometer J47
When QC counts! Ideal for food and beverage


  • Precision lab refractometer with traceable calibration
  • Stores measurement electronically
  • On-board temperature correction tables for sugar and water based samples
  • Excellent for QC when quality is truly important in the food and beverage product industry


All Instruments carry Rudolph's exclusive 20-Year Commitment to service your instrument.

Rudolph Research Analytical offers a comprehensive range of Preventive Maintenance and Service Programs. Rudolph has demonstrated a commitment to its customers by keeping installed instruments operational, not only for 20 years, but in some cases for over 40 years.

This long-term commitment to keeping Rudolph instruments running makes the cost of ownership, over the life of a Rudolph Instrument, one of the lowest in the laboratory market segment. At the date this document was published, there is no other laboratory instrument manufacturer guaranteeing service and technical support for 20 years.

View the entire 20-Year Service Guarantee.