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Gemini 3.8 Flash TTS
google / gemini-3-8-flash-tts
Commercial usePart of the Google API family — compare all Google models →

Google’s flagship creative text-to-speech model for high-fidelity, expressive voice generation. Gemini 3.8 Flash TTS supports natural-language voice design, voice cloning from around 30s of authorized audio, multi-speaker dialogue, and speech generation across 130 languages.

Pricing: Input 70 credits / 1M tokens (≈ $0.35), Audio Output 1,260 credits / 1M tokens (≈ $6.30) — both 30% below official pricing. Limited-Time Offer: these prices follow Google's promotional pricing and are valid until Dec 31, 2026. High-tier top-ups come with bonus credits that lower the effective price by about 10%.
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When true, filler words like "hmm" and "ahh," interjections, and natural background sounds will be added to the conversation.

Controls the randomness of the speech output. Higher values produce more creative and varied delivery, while lower values make the output more predictable and focused. Default value: 1

Output
output typeaudio

README

Complete guide to using google/gemini-3-8-flash-tts

Gemini 3.8 Flash TTS API – Create Custom Voices with 30-Second Voice Cloning

Build with Google Gemini 3.8 Flash TTS on Kie AI. Create original voices from natural language, replicate voices from short audio samples, and generate high-fidelity, expressive speech across 130 languages.

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Create and Replicate Voices with Gemini 3.8 Flash TTS API

Design Original Voices from Natural Language

Use Gemini 3.8 Flash TTS on Kie AI to create original voices from simple text descriptions. Define the voice you need through characteristics such as age, timbre, accent, tone, and delivery style, then use it across your text-to-speech workflows through Kie AI.

Design Original Voices from Natural Language

Replicate a Voice from Just 30 Seconds of Audio

With the Gemini 3.8 Flash TTS API on Kie AI, you can replicate a voice from approximately 30 seconds of authorized reference audio. Preserve the speaker’s recognizable vocal characteristics and generate new speech with the replicated voice for narration, characters, branded audio, and other applications.

Replicate a Voice from Just 30 Seconds of Audio

Key Features of Gemini 3.8 Flash TTS API on Kie AI

Generate Studio-Grade Speech with Gemini 3.8 Flash TTS API

Create clear, natural, and expressive audio with the Gemini 3.8 Flash TTS API. The model delivers high acoustic fidelity, natural cadence, and detailed acting nuance while following your voice directions closely. Use the Gemini 3.8 text-to-speech API for professional narration, character dialogue, podcasts, audiobooks, and other applications where voice quality and expressive delivery matter.

Design Custom Voices with Google Gemini 3.8 Flash TTS

Go beyond fixed voice presets with advanced Voice Design. Google Gemini 3.8 Flash TTS API lets you create original voice personas by describing the role, accent, tone, and vocal characteristics you want in natural language. Build distinctive character voices, narrators, or brand voices that better match the identity and creative direction of your application.

Direct Expressive Voice Acting Line by Line

Control how each line sounds instead of using one fixed speaking style. The Gemini TTS API supports turn-level directions for tone, pace, emotion, and delivery, along with natural vocal events such as laughter, sighs, breaths, coughs, and short pauses. This precise control helps developers create more realistic storytelling, dialogue, character voices, and expressive audio experiences.

Keep Voices Consistent Across Long-Form Audio

Generate longer speech without losing the identity of your selected voice. Gemini 3.8 Flash TTS API maintains consistent timbre, volume, voice characteristics, and acoustic tone across extended dialogue and multi-minute narration with minimal voice drift. This long-form stability makes the model well suited to audiobooks, podcasts, educational narration, and other continuous audio experiences.

Create Natural Multi-Speaker Dialogue with Gemini TTS API

Turn scripts into expressive conversations while keeping speakers clear and distinct. With Gemini 3.8 Flash TTS, developers can assign different voices and delivery styles to individual speakers, maintain natural turn-taking, and add vocal reactions throughout a scene. Use the Gemini TTS API to power podcasts, interactive characters, dramatic dialogue, and conversational voice experiences.

Generate Speech Across 130 Languages and Regional Accents

Build multilingual voice experiences with support for 130 languages, automatic language detection, regional accents, and minority dialects. The Google Gemini 3.8 Flash TTS API also supports IPA pronunciation overrides for words that need precise pronunciation. This gives developers more control when creating localized narration, global content, character voices, and speech applications for different markets.

How to Use Gemini 3.8 Flash TTS API on Kie AI

  • Step 1: Try Gemini 3.8 Flash TTS Free in the Playground

    Open the Kie AI playground to try Gemini 3.8 Flash TTS free online before integrating the API. Enter your text, explore different voices and speaking styles, and generate sample audio directly in your browser. It is a quick way to test how the model sounds and find the right voice for your project.

  • Step 2: Customize Your Voice and Speech

    Adjust your voice direction based on the audio experience you want to create. Use Gemini 3.8 Flash TTS to define voice characteristics, tone, accent, pace, emotion, and delivery style. You can refine your settings in the playground before using them in a production workflow.

  • Step 3: Get Your Kie AI API Key

    Create your Kie AI account and get your API credentials when you are ready to integrate. The Gemini 3.8 text-to-speech API lets developers bring expressive speech generation into SaaS products, AI agents, content tools, games, and other applications.

  • Step 4: Integrate Gemini 3.8 Flash TTS API into Your App

    Send your text and voice settings through the Gemini 3.8 Flash TTS API and receive generated audio for your application. Move from playground testing to production integration and build scalable voice experiences with the same Gemini TTS model.

Gemini 3.8 Flash TTS vs Gemini 3.8 Flash-Lite TTS

Gemini 3.8 Flash TTS is designed for applications where voice quality, expressive performance, and creative control matter most, while Gemini 3.8 Flash-Lite TTS focuses more on speed, throughput, and cost-efficient speech generation.

Gemini 3.8 Flash TTSGemini 3.8 Flash-Lite TTS
Primary FocusVoice fidelity & creative controlSpeed & cost efficiency
Supported Languages130101
Best ForCreative & professional audioHigh-volume speech generation
Long-Form NarrationSupportedSupported
Voice ReplicationSupportedSupported
Typical WorkloadsAudiobooks, dialogue, charactersVoice agents, read-aloud, bulk audio

What Can You Build with Gemini 3.8 Flash TTS API

Create AI Audiobooks with Gemini 3.8 Text-to-Speech API

Turn books, stories, and long scripts into expressive spoken audio with consistent voice quality. The Gemini 3.8 Flash TTS API maintains stable voice identity, natural pacing, and acting nuance across extended narration, making it well suited to AI audiobooks, serialized stories, educational audio, and other long-form text-to-speech applications.

Generate AI Podcasts and Multi-Speaker Audio

Build podcast-style conversations with distinct speakers, natural turn-taking, and individual delivery styles. Google Gemini 3.8 Flash TTS API can transform written scripts into engaging multi-speaker audio for AI podcasts, interviews, dialogue shows, and automated audio content without relying on one fixed narrator voice.

Build Character Voices for Games and Interactive Media

Create distinctive voices for game characters, virtual worlds, interactive stories, and entertainment apps. With custom Voice Design and expressive performance control, Gemini 3.8 Flash TTS lets developers define character personalities, accents, vocal styles, and emotional delivery to make digital characters feel more individual and engaging.

Power Expressive AI Voice Agents with Gemini TTS API

Give conversational AI more natural and responsive speech. The Gemini TTS API supports expressive delivery, conversational pacing, vocal reactions, and distinct voice identities for customer experiences, virtual assistants, interactive agents, and other voice-enabled SaaS products that need more than basic text-to-speech output.

Create Multilingual Dubbing and Localized Voice Content

Use the Gemini 3.8 Flash TTS API to generate localized speech across 130 supported languages, including regional accents and dialects. Developers can build multilingual dubbing, video localization, global learning content, and international media workflows while adapting pronunciation and vocal delivery for different audiences.

Design Brand Voices and Professional Audio Experiences

Create a recognizable voice identity for products, campaigns, apps, and digital experiences with Google Gemini 3.8 Flash TTS. Design a custom voice that matches your brand personality and reuse it across product narration, branded content, marketing audio, guided experiences, and other professional voice applications.

Why Choose Kie AI for Gemini 3.8 Flash TTS API

Access Gemini 3.8 Flash TTS and Flash-Lite TTS APIs on Kie AI

Use both Gemini 3.8 Flash TTS and Gemini 3.8 Flash-Lite TTS through Kie AI. Choose Flash TTS for high-fidelity, expressive voice generation or Flash-Lite TTS for high-volume, cost-efficient workloads—all within the same platform.

Try Gemini 3.8 Flash TTS Free Online

Test Gemini 3.8 Flash TTS free in the Kie AI playground before integrating the API. Enter your text, explore voice settings, and generate sample audio online to see how the model fits your application before moving into development.

Access Gemini TTS API and More AI Voice Models

Go beyond the Google Gemini 3.8 Flash TTS API and access other text-to-speech models through Kie AI. Developers can explore different TTS options for voice generation, narration, conversational AI, and other audio workflows without relying on a single model.

Get Affordable Gemini 3.8 Flash TTS API Pricing

Build AI voice features with affordable, usage-based access to the Gemini 3.8 Flash TTS API. Kie AI offers flexible pricing for developers and SaaS teams, making it easier to control text-to-speech costs as usage grows from testing to production.

Integrate and Manage Multiple TTS APIs in One Place

Connect the Gemini TTS API and other AI models through one developer-friendly platform. Kie AI simplifies API integration, usage management, and multi-model workflows, so you can spend less time managing separate providers and more time building your product.

Get Developer Support for Gemini 3.8 Text-to-Speech API

Get help throughout your Gemini 3.8 text-to-speech API workflow, from initial testing to production integration. Kie AI customer support can assist with API usage, integration questions, account issues, and other problems that may come up while building your application.

Frequently Asked Questions

Gemini 3.8 Flash TTS API provides access to Google’s flagship creative text-to-speech model for generating high-fidelity, expressive speech from text. It supports custom Voice Design, Voice Replication, multi-speaker dialogue, regional accents, long-form audio, and 130 languages.

You can access Gemini 3.8 Flash TTS through Kie AI to add AI speech generation to applications, SaaS products, content tools, voice agents, and other audio workflows. Test the model online first, then use the Kie AI API for integration.

Yes. Gemini 3.8 Flash TTS supports Voice Design, which lets you create a new voice from a natural language description. You can define characteristics such as age, vocal timbre, accent, and baseline delivery instead of choosing only from preset voices.

Gemini 3.8 Flash TTS supports 130 languages and automatically detects the input language. It also supports regional accents, minority dialects, and IPA-based pronunciation overrides for more precise speech generation.

Yes. Gemini 3.8 Flash TTS supports Voice Replication, allowing a voice to be recreated from approximately 30 seconds of authorized reference audio. It captures the speaker’s vocal characteristics and can reuse the replicated voice for new speech generation.

Gemini 3.8 Flash TTS focuses on maximum voice fidelity, acting nuance, and dialect coverage, while Gemini 3.8 Flash-Lite TTS focuses on high throughput, low latency, and cost efficiency. Flash supports 130 languages, while Flash-Lite supports 101.

Yes. The Gemini TTS API supports multi-speaker speech generation with separate speaker identities and turn-level instructions. This makes it suitable for dialogue, podcasts, storytelling, character conversations, and other multi-speaker audio applications.

Yes. You can try Gemini 3.8 Flash TTS free on Kie AI with available free credits. Test text-to-speech generation and explore the model before integrating the API into your application.

Gemini 3.8 Flash TTS API pricing on Kie AI is usage-based, so your cost depends on how much audio you generate. Check the latest Kie AI pricing for current rates before moving your TTS workload into production.