First Things First. Before you learn how to calculate and monitor your target training heart rate, you have to know your resting heart rate. Your resting heart rate is the number of times your heart beats per minute while it’s at rest. You can check it in the morning after you’ve had a good night’s sleep and before you get out of bed.
https://www.heart.org/HEARTORG/HealthyLiving/PhysicalActivity/FitnessBasics/Target-Heart-Rates_UCM_434341_Article.jsp
Now you’re ready to determine your target training heart rate. 1  Take your pulse on the inside of your wrist, on the thumb side. 2  Use the tips of your first two fingers (not your thumb) to press lightly over the blood vessels on your wrist.  Count your pulse for 10 seconds and multiply by 6 to find your beats per minute.
https://www.heart.org/HEARTORG/HealthyLiving/PhysicalActivity/FitnessBasics/Target-Heart-Rates_UCM_434341_Article.jsp
Heart rate is the speed of the heartbeat measured by the number of contractions of the heart per minute (bpm). The heart rate can vary according to the body's physical needs, including the need to absorb oxygen and excrete carbon dioxide. It is usually equal or close to the pulse measured at any peripheral point.
https://en.wikipedia.org/wiki/Heart_rate
1 Use the tips of your first two fingers (not your thumb) to press lightly over the blood vessels on your wrist.  Count your pulse for 10 seconds and multiply by 6 to find your beats per minute. You want to stay between 50 percent to 85 percent of your maximum heart rate. This range is your target heart rate.
https://www.heart.org/HEARTORG/HealthyLiving/PhysicalActivity/FitnessBasics/Target-Heart-Rates_UCM_434341_Article.jsp
Resting Heart Rate Table. A normal resting heart rate can range anywhere from 40 to 100 beats per minute. Below is a chart relating resting heart rate and fitness level. As can be seen on this chart, your resting heart rate can vary with your fitness level and with age — the fitter you are, generally the lower the resting heart rate.
http://www.topendsports.com/testing/heart-rate-resting-chart.htm
To get the most accurate reading, put your finger over your pulse and count the number of beats in 60 seconds. Your resting heart rate is the heart pumping the lowest amount of blood you need because you’re not exercising. If you’re sitting or lying and you’re calm, relaxed and aren’t ill, your heart rate is normally between 60 (beats per minute) and 100 (beats per minute).
http://www.heart.org/HEARTORG/Conditions/More/MyHeartandStrokeNews/All-About-Heart-Rate-Pulse_UCM_438850_Article.jsp
The normal resting adult human heart rate ranges from 60–100 bpm. Tachycardia is a fast heart rate, defined as above 100 bpm at rest. Bradycardia is a slow heart rate, defined as below 60 bpm at rest. During sleep a slow heartbeat with rates around 40–50 bpm is common and is considered normal. When the heart is not beating in a regular pattern, this is referred to as an arrhythmia.
https://en.wikipedia.org/wiki/Heart_rate
How Other Factors Affect Heart Rate. 1  Air temperature: When temperatures (and the humidity) soar, the heart pumps a little more blood, so your pulse rate may increase, but usually no more than five to 10 beats a minute.  Body position: Resting, sitting or standing, your pulse is usually the same.
http://www.heart.org/HEARTORG/Conditions/More/MyHeartandStrokeNews/All-About-Heart-Rate-Pulse_UCM_438850_Article.jsp
Even if you’re not an athlete, knowledge about your heart rate can help you monitor your fitness level — and it might even help you spot developing health problems. Your heart rate, or pulse, is the number of times your heart beats per minute. Normal heart rate varies from person to person.
http://www.heart.org/HEARTORG/Conditions/More/MyHeartandStrokeNews/All-About-Heart-Rate-Pulse_UCM_438850_Article.jsp
For a true measure of resting heart rate, it is important for the measurement to be taking accurately and under the best resting conditions. There is more information and instructions on how and when to measure resting heart rate.
http://www.topendsports.com/testing/heart-rate-resting-chart.htm
what is the normal heart rate chart
The normal heart rate chart is between 60 and 100 beats per minute.