Borg Scale: What It Is and How to Use the RPE 6-20 and CR10 Scales

What is the Borg scale?

The Borg scale is a rating of perceived exertion: a number you give to how hard your body feels it is working. Swedish psychologist Gunnar Borg developed it, and his 1982 paper on the psychophysical bases of perceived exertion is still the core reference. His 1998 book, Borg's Perceived Exertion and Pain Scales, describes the scales and how to use them in full.

When people ask "what is the Borg scale?", they usually mean one of two scales:

• The Borg RPE scale (6-20): rates overall exertion during exercise or physical work.
• The Borg CR10 scale (0-10): a general intensity scale for exertion, breathlessness, pain and other sensations.

According to the CDC, perceived exertion draws on what you feel during activity: a faster heart rate, faster breathing, sweating and muscle fatigue. It is subjective, but the CDC notes it can give a fairly good estimate of how hard you are actually working.

A note before we go further. Both scales are copyrighted and licensed, so this guide describes them in our own words and does not reproduce them. See where to get the official scale below.

Why does the Borg RPE scale run from 6 to 20?

The odd range is deliberate. Borg built the 6-20 scale so that ratings would rise roughly in line with heart rate during steady exercise. Multiply a rating by 10 and you get a rough heart-rate estimate, so 6 corresponds to about 60 beats per minute at rest and 20 to about 200 at maximal effort.

The CDC gives the same rule of thumb: an RPE of 12 suggests a heart rate of roughly 120 beats per minute. It also warns that this is only an approximation. Actual heart rate varies a lot with age and physical condition, so the borg scale 6-20 is a guide to effort, not a heart-rate monitor.

Short verbal labels sit beside some of the numbers, running from no effort at all at the bottom to the hardest effort possible at the top. You read the words, then pick the number that fits.

What is the Borg CR10 scale?

The Borg CR10 scale is a category-ratio scale. "Category" means it has verbal labels you can choose from. "Ratio" means the numbers are meant to behave like ratios, so a rating of 6 should feel about twice as intense as a rating of 3.

It runs from 0 (nothing felt) to 10, where 10 is anchored to the strongest sensation of that kind you have experienced. Unlike the 6-20 scale, the top is open. Borg's CR10 instructions allow decimals and allow ratings above 10 if a sensation is stronger than anything you have felt before.

BorgPerception's FAQ describes CR10 as the older and more widely used of its CR scales. It has been used clinically, in sport and training, and in ergonomics, to rate exertion, leg fatigue, breathlessness and aches in muscles and joints.

How do you use the Borg scale?

The official instructions come with the licensed scale. In general terms, a good rating follows a few principles:

• Rate your whole-body effort. Combine everything you feel, including breathing, heart rate, muscle strain and fatigue, rather than focusing on one sensation such as sore legs. (CR10 can be used for a single sensation, but then you say which one you are rating.)
• Be honest. Rate what you actually feel, not what you think you should feel or how you compare with others.
• Rate the feeling, not the pace. The number reflects how hard it feels, not how fast you are going or how heavy the load is on paper.
• Read the words, then pick the number. The verbal anchors are there to calibrate your answer.
• Use the same wording every time. Consistent instructions make ratings comparable across sessions and people.

If you want a quick, informal way to log effort, ViveLab's free 0-10 RPE scale lets you tap a number and see what it suggests. It is our own simple tool, not one of Borg's scales and not a substitute for the licensed version.

What do Borg ratings mean for exercise intensity?

On the borg scale of perceived exertion, the CDC links ratings of about 12-14 to moderate-intensity activity. Its example is a walker aiming for the "somewhat hard" level. If the walker rates the effort well below that range, they should speed up; if the rating climbs near the top, they should slow down.

The CDC page does not define light or vigorous bands on the 6-20 scale. A 2024 cross-sectional study by Grummt and colleagues proposed the following, based on a large sample:

Intensity	Proposed RPE (6-20)
Light	11 or lower
Moderate	12-14
Vigorous	15-17

Ratings of 18-20 sit above the vigorous band, toward maximal effort. The same paper notes that the American College of Sports Medicine (ACSM) uses slightly different bands, with light around 9-11, moderate around 12-13 and vigorous around 14-17.

This is general information, not medical advice. If you have a heart condition or take medicines that affect your heart rate, ask a health professional how hard you should exercise.

How are Borg ratings used in ergonomics?

Perceived exertion is also a practical way to judge how hard a job feels. The best-known link is the Strain Index for hand and wrist work, published by Moore and Garg in 1995.

Its first variable, intensity of exertion, is rated on five levels from light to near maximal. Cornell's reproduction of the method maps each level to Borg CR10 ratings. For example, a CR10 rating of 4-5 corresponds to "hard", the middle level. Because intensity carries the largest multiplier in the Strain Index, an honest effort rating matters a lot to the final score.

The UK HSE's ART tool for repetitive upper-limb tasks uses a similar idea. It asks how much hand force the worker uses and places force the worker describes as "strong" in its higher-risk categories.

Keep perceived exertion in its place. It is one input, not a risk score. A task that feels hard is worth investigating, and the follow-up should be a structured method that fits the job:

• For lifting and lowering, check the load with the NIOSH lifting equation calculator.
• For repetitive hand and wrist work, score the job with the Strain Index.
• For a wider view of force, posture and repetition risks, see our overview of common ergonomic hazards at work.

What are the limits of perceived exertion ratings?

The Borg scale is subjective, so two people doing the same task can rate it differently. The Grummt study found that age, sex, type of exercise, duration and fitness all influenced perceived exertion, especially at lower intensities.

The RPE x 10 heart-rate estimate is only approximate. The CDC says perceived exertion can be especially useful for people who take medicines that affect heart rate or pulse, because their heart rate may not reflect effort in the usual way.

Ratings are also easy to bias. Workers may understate effort to look capable, or overstate it if they think the rating will change their job. Clear, neutral instructions help.

At work, a single rating does not replace an assessment of posture, force, frequency and duration.

Where can you get the official Borg RPE and CR10 scales?

The official scales and their instructions belong to BorgPerception AB. According to BorgPerception's FAQ, the company holds copyright and trademark for the authorized scales and the instructions that go with them. It also warns against "modified" versions with changed words, added colors or pictures, because they can distort responses.

So if you need the borg scale for research, clinical work or a formal workplace program, get it from the source and follow its licence terms. Do not copy a version from the internet.

The Borg RPE scale® and Borg CR10 scale® are © Gunnar Borg; the official scales and instructions are available from BorgPerception AB.

Next steps

1. For a quick, unofficial effort rating, use ViveLab's simple 0-10 RPE scale. Remember it is our own unofficial scale, not Borg's.
2. If a task rates as hard, score it properly. Start with our guide to rating hand and wrist jobs with the Strain Index, or compare REBA, RULA and other assessment tools to pick the right method.
3. For research or clinical use, obtain the licensed Borg RPE and CR10 scales from BorgPerception AB.