How to Use the Eleven Flash v2.5 API: text to speech integration guide (2026)
Learn how to call the Eleven Flash v2.5 API on NamiFusion: parameters, pricing (from ≈$0.010) and runnable copy-paste code — try it in the playground first.
Eleven Flash v2.5 is a text to speech model by ElevenLabs: Our ultra low latency model in 32 languages. Ideal for conversational use cases. On NamiFusion you can try it in the playground (exact quote shown before you submit), then call it through one unified REST API — a typical run costs about $0.010.
TL;DR
· Task type: text to speech, provided by ElevenLabs
· Pricing: about $0.010 per typical run ($1 = 100 credits), pay-as-you-go
· Getting started: playground (exact quote before submit) → create an API key → one POST request
· Tunable parameters: 4 (see the table below)
· No platform watermark; commercial use allowed (per the Terms of Service)
What can you build with Eleven Flash v2.5?
Voiceovers and narration: generate multi-language voices for short videos, courses and ads.
Audio content production: turn articles, news and fiction into publishable audio at scale.
Product voice interfaces: consistent branded voices for apps and devices.
How do you call this API?
1. Sign up on NamiFusion and create a key on the API Keys page (free credits on signup).
2. Submit a task with the cURL example below, passing your key as a Bearer token.
3. Poll the task status with the returned task_uuid and read the output URLs when completed.
# 1) Submit — returns { "task_uuid": "..." }
curl -X POST "https://www.namifusion.com/api/v1/marketplace/run/eleven_flash_v2_5" \
-H "Authorization: Bearer YOUR_API_KEY" \
-H "Content-Type: application/json" \
-d '{
"input": {
"voice_id": "JBFqnCBsd6RMkjVDRZzb",
"language_code": "en",
"similarity_boost": 0.8,
"stability": 0.55
}
}'
# 2) Poll until status is "completed", then read the output URLs
curl "https://www.namifusion.com/api/v1/marketplace/run/tasks/TASK_UUID" \
-H "Authorization: Bearer YOUR_API_KEY"What parameters does it take?
voice_id (声音id): required
language_code (ISO 639-1语言code): optional
similarity_boost (Similarity Boost): optional, default 0.75
stability (Stability): optional, default 0.5
How much does it cost?
Pay-per-use in credits. A typical run costs about $0.010 ($1 = 100 credits); the exact price varies with parameters like resolution or duration, and the playground shows the exact quote before you submit.
Eleven Flash v2.5
Fast, affordable text-to-speech with no cold starts and natural voice quality.
Flash V2.5 is an ElevenLabs text-to-speech model available on WaveSpeed AI for developers and teams that need reliable, production-ready speech generation. It combines low latency, natural pronunciation, multilingual voice options, and fine-grained voice control, making it a strong choice for narration, voiceovers, and scalable audio content pipelines.
🚀 Key Features
- No cold starts: Well suited for real-time and high-frequency workloads where responsiveness matters.
- Natural-sounding speech: Produces clear pronunciation, smooth pacing, and expressive delivery for polished audio output.
- Rich voice library: Supports a broad set of built-in multilingual voices as well as custom
voice_idvalues. - Fine voice control: Adjust
similarityandstabilityto balance speaker likeness, clarity, and delivery consistency. - English normalization support:
use_speaker_boostimproves reading quality for numbers, dates, times, and measurements in English. - Cost-efficient scaling: Transparent per-character pricing makes it practical for batch generation and commercial content workflows.
🛠️ Technical Specifications
| Item | Details |
|---|---|
| Model Name | Flash V2.5 |
| Model ID | elevenlabs/flash-v2.5 |
| Model Type | Text-to-Speech（TTS） |
| Input | Text |
| Output | Audio |
| Output Format | MP3 |
| Maximum Input Length | 10,000 characters |
| Billing Unit | Charged per character; price is shown per 1,000 characters |
| voice_id | Default: Alice; supports built-in and custom voice IDs |
| similarity | 0.0–1.0, default 1.0; controls voice similarity and enhancement strength |
| stability | 0.0–1.0, default 0.5; controls consistency of delivery |
| use_speaker_boost | Boolean, default true; improves English text normalization for numbers and units |
| Pause Control | Use <#x#> between words to insert pauses from 0.01 to 99.99 seconds |
| Latency | Optimized for fast generation with no cold starts; actual inference time depends on text length and load |
| Language Support | Multilingual voice support, with strong English number and date reading performance |
Sample Prompts
Note: This is a text-to-speech model, so the examples below are sample input scripts rather than image prompts.
Welcome to our product demo. Today we'll walk through the key features, pricing, and setup in under two minutes.Your appointment is scheduled for 3:45 PM on September 18th. Please arrive 10 minutes early.The package weighs 2.5 kilograms and will arrive in 3 to 5 business days.<#0.5#>Thank you for your order.
💰 Pricing
| Item | Price |
|---|---|
| Generated speech per 1,000 characters | $0.05 |
FAQ
Can I try it for free first?+
Signup gives you free credits, but they currently apply only to selected in-app face-swap features — this model is pay-as-you-go. The playground still lets you try it without code, with the exact quote shown before you submit.
Can I use the output commercially? Is there a watermark?+
Yes, outputs are yours to use commercially, and NamiFusion adds no platform watermark — subject to the Terms of Service and applicable law.
What is the content policy?+
NamiFusion is an unfiltered engine: no arbitrary restrictions and NSFW-friendly, but illegal content and non-consensual use of real people are prohibited — see the Terms of Service.
How long does a Eleven Flash v2.5 task take?+
It depends on parameters — images usually take seconds, videos tens of seconds to minutes. The API returns a task_uuid for polling.
What are the resolution and duration limits?+
See the parameter table above — each model lists its available resolution and duration options there and in the playground.