Here is a handy resource to determine the length of completed narrations:

SPEECH COUNT
    - Average person reads 3 words per second (range is 2 to 4)
    - Average person reads 88 words per half-minute (range is 60 to 120)
    - Average person reads 170 words per minute (range is 135 to 215)
    - Average person reads 10,320 words per hour (range is 8625 to 12,030)
LINE COUNT (12 point Arial, double-spaced, margin-to-margin)
    - Average number of lines per page: 21
    - Average number of lines per 30-second spot: 7.5
    - Average number of lines per 60-second spot: 15
WORD COUNT (12 point Arial, double-spaced, margin-to-margin)
    - Average words per line: 13 (range is 8 to 18)
    - Average words per page: 273 (range is 168 to 378)


Courtesy of EDGE STUDIO-Helping Voice-Talent Build Careers
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