Cost per course hour: TTS narration budgeting — Audra

Course platforms budget per finished hour of instruction, so that is the unit this post prices. The conversion from course-hours to characters is stable enough to plan an LMS catalog against.

Characters in one course-hour

Instructional narration runs slower than conversational speech: a finished hour of course audio is about 45k characters of script. That figure is the same one behind the 20-lesson course example in our pricing calculator — 180k characters, roughly four hours of lessons.

Worked example: a 10-course catalog

A training shop migrating 10 courses × 6 finished hours each is looking at 60 course-hours — 2.7M characters of narration in total. Pricing the whole catalog up front is one multiplication.

Engine choice per module type

• Essential (1.0×) — standard lesson narration, $1.13 per finished course-hour.
• Pro (2.0×) — module intros or sales-flavored promo segments, $2.25 per course-hour.
• Re-render a single 12-minute lesson (~9k chars) for $0.23 on Essential when content changes.

This post deliberately leaves podcast-episode math to /blog/cost-per-podcast-episode-tts; the course pipeline itself is covered at /blog/course-narration-tts-api.

Next steps

• Start here: /blog/course-narration-tts-api
• Then: /calc
• Reference: /pricing
• More Audra guides: /blog