Gemini 3.1 Flash TTS is a text-to-speech model launched by Google, ranking first in the Artificial Analysis TTS rankings with 1211 Elo points. Supports 70+ languages, natural language control of audio tags, multi-speaker dialogue Audio Profiles timbre fingerprinting and mandatory SynthID watermark protection.

Gemini 3.1 Flash TTS: Google’s high-quality text-to-speech model

Core parameters and statistics

Project	Details
Product Name	Gemini 3.1 Flash TTS
Product Type	Text-to-Speech (TTS) Model
Delivery Form	Gemini API / Google AI Studio / Vertex AI / Google Vids
Supported languages	70+ languages
Sound Quality Rating	Artificial Analysis TTS Ranking 1211 Elo
Cost Quadrant	High Quality/Low Cost Optimum Quadrant
Security mechanism	Forced SynthID invisible watermark
Target users	Developers, enterprise users, Workspace users

Gemini 3.1 Flash TTS scored 1211 Elo points in the independent evaluation of Artificial Analysis, ranking first in the TTS rankings and in the optimal quadrant of "high quality-low cost". This means that it is comparable to top commercial TTS engines in terms of natural sound quality, but the inference cost is significantly lower than similar competing products. For teams, this means a lower threshold for trial and error and greater speech generation capabilities at scale.

User and market recognition

Gemini 3.1 Flash TTS ranked first on the Artificial Analysis TTS rankings with 1211 Elo points and was rated as a product in the "High Quality and Low Cost" quadrant. The evaluation covers mainstream commercial and open source TTS models on the market, and the ranking reflects their comprehensive advantages in sound quality, naturalness and cost efficiency.

In terms of ecological coverage, Google reaches users through three paths: developers make direct calls through Gemini API and Google AI Studio; enterprise users obtain enterprise-level security and compliance capabilities through Vertex AI; Workspace users can use TTS functions directly in Google Vids without additional integration. This layered coverage strategy lowers the access threshold for users with different technical backgrounds.

Cost advantage

• C-side/Individual: Usually a free version is provided to experience the core functions, and high-frequency use requires a paid package subscription.
• API/Developer: Billed by call volume, suitable for development teams that can be flexibly integrated into their own systems.
• Enterprise/Privatized: Contact the business owner for customized quotation and deployment plan. The specific price is subject to the official real-time pricing page.

Main functions

• Audio Tags Control: Embed text input through natural language instructions to precisely control voice style, speaking speed and expression. Developers can change the voice expressiveness with text descriptions without complicated parameter tuning.
• Multi-speaker dialogue: Natively supports multi-character dialogue scenarios, and characters can maintain voice consistency in multiple rounds of interaction. Suitable for multi-role content production such as podcasts, audiobooks, and customer service conversations.
• Audio Profiles timbre fingerprint: Create a unique timbre configuration for each character, supporting director's notes to switch intonation, accent and emotional state. Ensure sound consistency across projects and platforms.
• Scene Director: Define contextual backgrounds and dialogue instructions to help characters stay "in play" and interact naturally. Suitable for game NPC, film and television dubbing and other scenes that require situational performance.
• SynthID watermark protection: All generated audio is automatically embedded with SynthID invisible watermark, supporting reliable detection and traceability of AI-generated content to prevent the risk of deep forgery.
• 70+ Language Support: Localized voice output covering major languages ​​around the world, maintaining a consistent sound quality level for each language.

Expert Viewpoint: Audio tags + Audio Profiles + Scene Director form a progressive control system from "pronunciation" to "performance" to "situation". Developers no longer need to adjust voice parameters frame by frame, but can describe their needs in words like a director. This not only lowers the technical threshold for TTS integration, but also allows content creators with non-technical backgrounds (such as screenwriters and game planners) to directly participate in voice production, reducing cross-position communication costs.

Model and version evolution

Gemini 3.1 Flash TTS is currently in the Developer Preview stage and is open through the Gemini API and Google AI Studio. Google also provides previews through Vertex AI on the enterprise side and Google Vids integration on the Workspace side.

From the perspective of version history, it has gone through the early basic TTS capability verification (0.9 preview version) to the current full-featured preview version (1.0) that supports audio tags and multi-speaker Audio Profiles. The pricing and SLA of the official version are subject to Google’s official announcement.

Technical advantages

• High sound quality - low-cost technical foundation: Gemini 3.1 Flash TTS is optimized based on the Gemini 3.1 Flash backbone model and inherits the architectural advantages of the Flash series in inference efficiency and cost control. In the Artificial Analysis test, its inference cost is only a fraction of that of competing products without losing the sound quality to head products.
• NLP-driven control of audio tags: Unlike traditional TTS that requires adjusting SSML tags or numerical parameters, audio tags directly describe control intentions in natural language, and the underlying model understands the semantics and maps them to acoustic features. This significantly reduces the learning curve for voice customization.
• SynthID watermark project implementation: Google DeepMind's SynthID watermark technology embeds imperceptible logos directly in the audio spectrum, does not reduce sound quality, and is resistant to common post-processing such as compression and noise reduction. This is one of the most mature AI audio traceability solutions in the industry.
• End-to-end cloud architecture: Get low-latency streaming voice output through the Gemini API without the need for local GPUs or specialized hardware. This eliminates users’ self-built inference costs and operation and maintenance burdens.

How to use

Entrance	Applicable people	Description
Google AI Studio	Developer	Preview and test through the web interface, use configurable controls to adjust scene settings, speaker properties, and audio tags, and export to Gemini API code when completed
Gemini API	Developer	Programming interface integration, supports fine control of all TTS parameters, suitable for custom application development
Vertex AI	Enterprise users	Enterprise-level security, compliance and private deployment, providing SLA guarantee
Google Vids	Workspace users	Use TTS speech generation directly in video editing tools without coding

Typical developer usage process: Log in to Google AI Studio → Select the Gemini 3.1 Flash TTS model → Configure the scene/speaker/audio tag → Test the voice effect → Export the API code → Integrate into the application.

Product Pricing

Gemini 3.1 Flash TTS is currently in preview, and Google AI Studio provides free trial credits. The official version pricing adopts a pay-as-you-go billing model, and the specific rates are subject to the official Google Cloud pricing page.

From the perspective of competing products, Artificial Analysis classifies it into the "high quality and low cost" quadrant, which means that at the same sound quality level, its unit production cost is significantly lower than professional TTS platforms such as ElevenLabs and Play.ht. For large-scale scenarios where tens of thousands of minutes of voice are generated every day, this cost advantage will directly determine the feasibility of the solution.

Application scenarios

• Audiobook and Podcast Production: Use audio tags to precisely control narration style and character dialogue to create a multi-character immersive narrative experience for audiobooks. Scene Director helps maintain a consistent presentation style for long-form content.
• Virtual Assistant and Customer Service System: Construct a unique timbre fingerprint for AI customer service, and adjust the intonation in real time to adapt to different service scenarios through natural language instructions. Multi-speaker support enables seamless role switching between customer service and users.
• Game NPC dubbing: Assign exclusive Audio Profiles to game characters and define scene backgrounds to ensure that NPCs maintain voice consistency and situational performance in multiple rounds of interactions, significantly reducing the iteration cost of game dubbing.
• Educational content localization: Support the production of localized audio teaching materials in 70+ languages, and adjust the speaking speed and pronunciation style through director notes to adapt to learners of different ages. Suitable for multilingual online education platforms.
• Accessibility Assistive Service: Integrate highly natural speech to provide screen reading and auxiliary reading functions for visually impaired users. SynthID watermark ensures that the content source is transparent and trustworthy, and meets accessibility compliance requirements.

Applicable people

• Application Developers: Technical teams who need to integrate high-quality TTS into their own products through APIs, especially in scenarios that require multi-language, multi-role, and fine-grained control of voice expressiveness.
• Content Creators: Podcasters, audiobook producers, and video creators who want to use AI to replace human voiceover recording while maintaining detailed control over voice style.
• Enterprise AI Team: Large-scale, high-reliability, and compliant TTS services are required. Vertex AI's enterprise-level capabilities are the reason for differentiation.
• Not suitable for the crowd: Users who need to run offline and locally (Gemini 3.1 Flash TTS is a cloud API service); scenarios that require extreme real-time performance in voice delay (such as real-time simultaneous interpretation, the preview version does not disclose the delay index); users who need voice cloning or custom timbre training (Voice Cloning capability is not currently provided).

Summary and Outlook

Gemini 3.1 Flash TTS is an important product launch by Google in the TTS field. With a sound quality score of 1211 Elo and a "high quality at low cost" cost positioning, it has carved out a clear differentiated position in the crowded TTS market. The combination of audio tag Audio Profiles and scene director elevates TTS control from parameter adjustment to natural language director level, lowering the threshold for use and expanding the creative space.

Not suitable for boundaries: Does not support offline deployment and relies on Google Cloud infrastructure; SLA and complete pricing have not been disclosed during the preview period; in-depth customization functions such as voice cloning are not supported; the coverage quality of niche languages ​​such as Chinese dialects and minority languages ​​has not been disclosed.

Procurement/Adoption Risk Assessment: It is currently in the developer preview stage, and the pricing and functional boundaries of the official version may change; TTS output is forced to embed SynthID watermarks, which may restrict some business scenarios that require completely watermark-free output; large-scale commercial use relies on the Google Cloud ecosystem, and there is a risk of platform lock-in. It is recommended to fully test the adaptability of core scenarios during the preview period and wait for the official version to be released before making large-scale production deployment decisions.

Related tools: ElevenLabs, udio

Version Info

• Developer Preview ：Developer preview available via Gemini API and Google AI Studio, with support for audio tags, multi-speaker conversation Audio Profiles, and SynthID watermarks. （2026-04）
• early preview ：Early developer preview version, basic TTS capability verification. （2026-02）