VoiceNotes AI
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Free Text to Speech Calculator

Paste your script to instantly calculate speech duration, clip count, and estimated generation cost. No sign-up required.

0 / 5,000 chars

Characters

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Words (est.)

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Duration

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Clips (500 chars)

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Cost / Gen

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at $0.015 / 1K chars

Monthly Cost

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Paste your script above to see instant results.

Duration Reference Table

Quick lookup for how long a script will take at each speech speed.

WordsChars (est.)Slow (130 WPM)Normal (150 WPM)Fast (180 WPM)
5025023s20s17s
10050046s40s33s
1507501m 9s1m50s
2001,0001m 32s1m 20s1m 7s
5002,5003m 51s3m 20s2m 47s
1,0005,0007m 42s6m 40s5m 33s

TTS Cost Reference Table

All figures at $0.015 per 1,000 characters — a typical rate for high-quality AI TTS APIs.

CharactersClips (500-char)Cost (est.)
5001$0.0075
1,0002$0.015
2,5005$0.037
5,00010$0.075
50,000100$0.750
100,000200$1.500

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What is TTS Duration Calculator?

A text-to-speech calculator is a free tool that estimates how long a piece of text will take to read aloud as AI-generated audio. Paste your script and the calculator instantly shows the estimated speech duration, number of 500-character clips needed, and the approximate generation cost. Content creators use it to plan TikTok and Shorts voiceovers, estimate budgets before bulk generation, and decide how to split long scripts into clips. At a normal speaking pace of 150 words per minute, every 750 characters produces roughly one minute of audio. This calculator handles all the math so you can focus on your content.

How it works

  1. 1Paste your script into the text area. The character count and all results update instantly as you type — no button to click.
  2. 2Choose a speech speed — Slow (130 WPM), Normal (150 WPM), or Fast (180 WPM) — to match your intended AI voice. Optionally enter your monthly generation count to see an estimated monthly cost.
  3. 3Use the results to decide how to split your script into clips, plan your video timeline, and budget your TTS usage.

Frequently Asked Questions

How many characters is 1 minute of speech?

At a normal speaking pace of 150 words per minute (WPM), and assuming approximately 5 characters per word, 1 minute of speech requires around 750 characters. At a slow pace (130 WPM) that is about 650 characters, and at a fast pace (180 WPM) it reaches roughly 900 characters.

How do I split long text for TTS?

Split at natural pause points — sentence endings, paragraph breaks, or scene transitions. Each clip should ideally be one to two sentences. For TikTok-style voiceovers, clips under 500 characters keep the energy punchy and let you control pacing in your editor.

How much does text-to-speech cost per 1,000 characters?

At the standard rate used in this calculator ($0.015 per 1,000 characters), a single 500-character generation costs less than a penny ($0.0075). A month of 100 daily generations at 500 characters each would cost roughly $0.75.

How many clips does a 60-second video need?

At 150 WPM, 60 seconds of speech requires about 750 characters. Since each TTS clip allows up to 500 characters, a 60-second voiceover typically needs 2 clips. You then stitch them together in your video editor.

What is the difference between slow, normal, and fast speech?

Slow (130 WPM) mimics a deliberate, educational delivery — good for explainer content. Normal (150 WPM) matches natural conversational speech — the most common choice for TikTok and Shorts. Fast (180 WPM) suits energetic, high-cut content where you need maximum information density.

Can I use this calculator to plan my TikTok TTS budget?

Yes. Enter your typical script length, set your speed, and enter how many videos you generate per month. The calculator shows your estimated monthly cost. Most creators generating a few hundred videos per month will spend less than $1 on TTS generation.

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