img_uuid until completion.Veo 3.1 Fast API for Production Video Workflows
Access Google's Veo 3.1 Fast model through the independent GoEnhance API. Submit text, first and last frames, or up to three reference images, then track the asynchronous task by
Create an API Key
Three Input Modes Selected by Your Request
Prompt-Only Text to Video
Send model: veo3_1_fast with a required prompt and no image inputs. Choose a 4, 6, or 8 second duration, 720p or 1080p quality, and a supported ratio.
First and Last Frame Control
Add image_url for a first frame and optionally image_end_url for a last frame. A last frame cannot be used without the first frame.
Reference-Guided Video
Provide up to three URLs in ref_imgs. Reference mode cannot be combined with first or last frames and is fixed to 8 seconds at 16:9.
Validate mode-specific fields before submitting a billable asynchronous task.
Veo 3.1 Fast API Capabilities and Validation
Exact Model ID
Set <code>model</code> to <code>veo3_1_fast</code>. The model value and <code>prompt</code> are required.
4, 6, or 8 Seconds
The <code>duration</code> field accepts 4, 6, or 8 and defaults to 4. Reference mode requires 8 seconds.
720p or 1080p
Set <code>quality</code> to <code>720p</code> or <code>1080p</code>. Both use the same documented rate.
Automatic or Explicit Ratio
Choose <code>auto</code>, <code>16:9</code>, or <code>9:16</code>. Reference mode requires 16:9.
Optional Generated Audio
Set <code>generate_audio</code> explicitly. The GoEnhance endpoint defaults to <code>false</code>, and audio uses a higher per-second rate.
Mutually Exclusive Image Modes
Do not combine <code>ref_imgs</code> with <code>image_url</code> or <code>image_end_url</code>; the request is rejected.
Pricing is based on generated duration and whether the request asks the model to create an audio track.
Veo 3.1 Fast API Pricing
Video Without Generated Audio
5.4 tokens per generated second, equal to $0.108 per second at the documented $0.02 per token.
Video With Generated Audio
8.06 tokens per generated second, equal to $0.1612 per second at the documented $0.02 per token.
Estimate Every Request
Multiply the selected per-second rate by the requested duration. The published rate is the same for 720p and 1080p.
Integrate Veo 3.1 Fast in Three Steps
1
1. Validate the Input Mode
Choose prompt-only, first/last-frame, or reference-image generation. Enforce the mode-specific duration and ratio rules before submission.
2
2. Submit and Persist img_uuid
POST to
https://api.goenhance.ai/api/v1/videos/generations with bearer authentication, then save data.img_uuid from a successful response. 3
3. Resolve the Terminal Result
Poll
GET https://api.goenhance.ai/api/v1/jobs/detail?img_uuid=... or process callback events idempotently until the task succeeds or fails.Build repeatable video workflows around prompts and media you are authorized to use.
Developer Use Cases for Veo 3.1 Fast
Campaign Concept Clips
Turn structured creative briefs into short video concepts for human review and downstream editing.
Product Motion Studies
Use approved product frames or references to prototype movement, camera direction, and atmosphere.
Storyboard Previsualization
Generate concise shot studies from scene descriptions before committing to a finished production.
Localized Video Pipelines
Parameterize prompts and route outputs through market-specific review, storage, and approval steps.
Reference-Guided Concepts
Use up to three approved reference images to guide an eight-second 16:9 concept clip.
Automated Media Systems
Connect task submission, durable IDs, callbacks, asset storage, and editorial gates in your own application.
Answers about Google API search intent, pricing, inputs, validation, and asynchronous delivery.