How to Use the Veo 3.1 Text to Video API: text to video integration guide (2026)

Veo 3.1 Text to Video is a text to video model by Google: Storytelling Powerhouse. 1080p generation featuring dialogue lip-sync and subject consistency (R2V). 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 $3.20.

TL;DR

· Task type: text to video, provided by Google

· Pricing: about $3.20 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: 7 (see the table below)

· No platform watermark; commercial use allowed (per the Terms of Service)

What can you build with Veo 3.1 Text to Video?

Short-form video and ad clips: go from a prompt or a single image to publishable motion content.

Product demos and concept previews: validate storyboards and visual direction cheaply before any shoot.

A social content factory: batch vertical clips and ride trending topics fast.

Remixing existing assets: image-to-video brings static work to life and extends its lifespan.

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/google/veo3.1/text-to-video" \
  -H "Authorization: Bearer YOUR_API_KEY" \
  -H "Content-Type: application/json" \
  -d '{
  "input": {
    "prompt": "Cinematic tracking shot of a futuristic cyberpunk night market in Tokyo, wet pavement reflecting vibrant neon pink and blue lights. A mysterious figure in a trench coat walks away from the camera into the steam rising from food stalls. Atmospheric lighting, photorealistic 8k textures, shallow depth of field. Audio: Heavy rain pouring, distant police sirens wailing, and the sizzling sound of street food cooking.",
    "aspect_ratio": "16:9",
    "duration": "8",
    "resolution": "1080p",
    "generate_audio": true,
    "negative_prompt": "cartoon, illustration, sketch, blurry, low resolution, distorted audio, silent, shaky camera, overexposed, low quality",
    "seed": 0
  }
}'

# 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?

prompt (Prompt): required

aspect_ratio (Aspect Ratio): optional, default "16:9"

duration (Duration): optional, default "8"

resolution (Resolution): optional, default "1080p"

generate_audio (Generate Audio): optional, default true

negative_prompt (Negative Prompt): optional

seed (Seed): optional

How do you write prompts for Veo 3.1 Text to Video?

1. Subject first: lead with the actor and action, then add environment, lighting and style ("an astronaut sprinting through a neon street in the rain, cinematic, shallow depth of field").

2. Concrete nouns beat stacked adjectives: "85mm portrait lens, golden-hour backlight" works far better than "very beautiful, ultra high quality".

3. Change one variable per iteration: pin the seed to reproduce a result, tweak a single phrase at a time so you know what actually moved the output.

4. State negatives positively: instead of "no blur", ask for "sharp focus, crisp details".

How much does it cost?

Pay-per-use in credits. A typical run costs about $3.20 ($1 = 100 credits); the exact price varies with parameters like resolution or duration, and the playground shows the exact quote before you submit.