Kokoro TTS
The cheapest text-to-speech model on Renas AI at $0.02 per 1,000 characters. 19 voices, American English + Mandarin Chinese, speed control from 0.1x to 5x. Lightweight 82M-parameter architecture for fast inference at scale.
Model Specs
- Released
- Dec 2024
- Voices
- 20
- Languages
- 9
- Max characters
- 5K
- Modalities
- textaudio
About this model
Kokoro TTS is a lightweight text-to-speech model — only 82 million parameters — designed for parameter efficiency and cost-effective deployment at scale. On Renas AI, Kokoro TTS costs $0.02 per 1,000 characters (50,000 characters per dollar), making it the cheapest TTS option on the platform. The model offers 19 voices (10 female with `af__` prefix, 9 male with `am__` prefix) and supports American English plus Mandarin Chinese as separate language models.
A distinctive feature is fine-grained speed control: 0.1x to 5x playback rate adjustment, useful for accessibility workflows (slow narration), audio book production (variable pacing), or rapid-listen content (sped-up audio for review). The output format is WAV, which preserves audio quality at the cost of larger file sizes — convert to MP3 in post-processing if file size matters for delivery. Commercial use is permitted under Kokoro's licensing.
Reach for Kokoro TTS when (a) you're producing high-volume audio content where per-character cost matters most, (b) the language is American English or Mandarin Chinese (Kokoro's native targets), (c) you need speed control for accessibility or pacing, or (d) you want fast inference for batch workflows. For 70+ language coverage or premium voice cloning, ElevenLabs v3; for emotion control + voice cloning, Dia TTS; for inline emotion tags + Llama-based architecture, Orpheus TTS.
Key Strengths
Cheapest TTS on Renas
$0.02 per 1,000 characters — 50,000 characters per $1. About 2.5x cheaper than Orpheus ($0.05) and 5x cheaper than ElevenLabs ($0.10). Makes high-volume audio content workflows economical.
19 voices across genders
10 female voices (af__ prefix) and 9 male voices (am__ prefix) — variety for narrators, character work, and content where voice diversity matters.
Speed control (0.1x to 5x)
Adjust playback rate for accessibility (slow narration for hearing-impaired users), audio book pacing (variable speed for emphasis), or rapid-listen review (sped-up content for skimming). Unique granular control among Renas TTS models.
Lightweight 82M-parameter architecture
Smaller than competing TTS models (typically 1B+ parameters) — translates to faster inference and lower compute cost. Engineered for parameter efficiency rather than raw capability.
American English + Mandarin Chinese
Two of the largest content audiences globally. Separate language models on fal.ai means each is optimized rather than a generalist multilingual model.
Commercial use permitted
Kokoro's licensing allows commercial use. Combined with Renas's commercial rights, all Kokoro audio you generate is yours to use in commercial projects without additional licensing.
Voice synthesis capabilities
Available voices, languages, and expressive controls.
How it compares
Kokoro TTS is the cost leader. Compare against alternatives based on language coverage, voice quality, and feature requirements.
| vs. Model | Verdict | Outcome |
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Pros
- Cheapest TTS on Renas ($0.02 per 1K chars)
- 19 voices (10 female + 9 male)
- Speed control 0.1x to 5x — unique granular control
- Lightweight 82M-parameter architecture for fast inference
- American English + Mandarin Chinese native support
- Commercial use permitted
- WAV output preserves audio quality
Things to consider
- Limited to 2 languages (American English + Mandarin Chinese)
- No emotion control or expressive features
- No voice cloning capability
- No multilingual model (separate models per language)
- WAV output has larger file sizes than MP3 — convert if delivery size matters
- 82M params = lower fidelity than premium 1B+ TTS models
Best use cases
High-volume audio content
Bulk audio narration for blog posts, product descriptions, news summaries. The $0.02/1K char rate makes scale economical — a 10,000-word article (~50K chars) costs $1.
Podcast intro/outro generation
Consistent intros and outros across episodes. Pick a Kokoro voice, write the script, generate hundreds of variations cheaply.
Audio book and long-form narration
Speed control + cost efficiency makes Kokoro suitable for long-form audio book or narration projects. Adjust pace for emphasis or chapter pacing.
Accessibility workflows
Audio descriptions of visual content, screen reader alternatives, slow-narration content for cognitive accessibility. Speed control adapts to user needs.
Mandarin Chinese content
Mandarin Chinese is one of Kokoro's two native languages. Useful for content workflows targeting Chinese-speaking audiences without paying for ElevenLabs's multilingual premium pricing.
Educational content audio
Course material narration, tutorial voiceovers, explainer audio. Cost-efficient for high-volume educational pipelines.
How to use it on Renas AI
- 1
Step 1
Open the AI Voice tool in TTS mode
Navigate to AI Voice in the Renas dashboard, then switch to Text-to-Speech mode. Pick Kokoro TTS from the model selector — it's marked as the budget Kokoro variant.
- 2
Step 2
Pick voice and language
Choose from 19 voices — 10 female (af__) or 9 male (am__). Pick American English or Mandarin Chinese based on your content language. Both are separate model endpoints.
- 3
Step 3
Write or paste your text
Enter the text you want narrated. For long content, the per-character pricing means you can submit substantial scripts cheaply — a 10K-word article costs about $1 raw. Adjust speed (0.1x-5x) if needed.
- 4
Step 4
Generate, review, deploy
WAV output goes to your asset library. Convert to MP3 with Renas audio tools if file size matters for delivery. Embed in podcasts, videos, or content workflows.
Pricing
Pricing on Renas AI
Pay-as-you-go credits, no API keys, no rate limits.
Frequently asked questions
Cheapest text-to-speech on Renas
Use Kokoro TTS with your Renas AI subscription credits — no API key, no setup, no per-seat fees.
Try Kokoro TTS