Shorts voiceover: how many characters fill 15, 30, 45 and 60 s
Planning table from script length to seconds and TTS cost, with the 15 characters per second assumption labeled and a way to measure the real value.
Before voicing a script you want to know if it fits the Short. The table below uses 15 characters per second as an assumption for a normal narration pace. Your voice and script will differ, so measure once and replace the number.
Planning table
| Target | Characters | TTS cost |
|---|---|---|
| 15 s | 225 | $0.0107 |
| 30 s | 450 | $0.0214 |
| 45 s | 675 | $0.0321 |
| 60 s | 900 | $0.0428 |
Measure your own pace
Ask TTS for word timestamps. Divide the character count by the last word's end time and use that figure next time.
Code to compute characters for a target:
rate = 15 # characters per second, assumed
price = 0.0475 / 1000
for secs in (15, 30, 45, 60):
chars = secs * rate
print(secs, "s", chars, "chars", round(chars * price, 4))
Sources
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