For a standard text message, 153 characters will usually equal approximately one credit.
The standard font is Ariel, size 13.
You'll be able to see if you're using the standard font when you're writing your SMS as you'll see how many characters you've used and how many per credit you have.
Is the SMS signature included in credits used?
Yes, the SMS signature is included in the number of credits used. You can see how many characters your signature has when you're writing your SMS.
Why is the number of credits different per recipient?
Although an SMS message may be the same length for multiple recipients, the credits being used may differ, depending on the carrier that is receiving the message.
Our SMS provider's (Vonage) pricing fluctuates based on carrier costs, which is reflected in Arbor with a decimal point based on each credit used. So some messages to guardians may be 1.2 credits, whereas the same message to a different guardian may be 1.4 credits.