The formula
credits = rate_per_second(audio on | audio off) × seconds- rate_per_second(audio)
- a two-value lookup: 20 credits silent, 40 with native audio on VEO 3.1. The toggle replaces the rate for the whole clip — it is never charged on only part of it.
- seconds
- the clip length. These models sell fixed durations (4s, 6s, 8s), so the toggle is usually the only variable you control.
Worked example — An 8-second shot with dialogue on VEO 3.1
- 1.audio-on rate = 40 credits per second
- 2.seconds = 8
- 3.40 × 8
= 320 credits, against 160 for the same shot silent
Sound that multiplies versus sound that adds
There are two ways to get sound onto an AI clip and they are priced on opposite principles. Native audio multiplies: the model generates picture and sound together and charges a higher rate for every second. Added audio adds: you generate a voiceover or a music bed as its own item, then pay a flat fee to lay it onto the video, and the video's own price never moves.
Multiplication wins on very short clips and loses on long ones. On VEO 3.1 the audio premium is 160 credits for an 8-second shot — and it would be 1,200 credits if that rate ran for a minute. The additive route's attach fee does not move with length at all.
What native audio buys that the additive route cannot is synchronisation: sound generated with the picture is matched to what is happening on screen. That is a creative argument rather than a pricing one, and it is worth knowing which of the two you are paying for.
The audio toggle, and the additive alternative
Every figure below is computed from Versely's live price matrix — the same matrix the app quotes you from before it charges. These are prices, not verdicts: the buyer's guides are where models get ranked.
The audio toggle across 9 models
Ordered by how steep the toggle is. The premium is no more a fixed multiple than the resolution premium is.
| Model | Silent | With audio | Multiplier | 8s with audio |
|---|---|---|---|---|
| VEO First Last Frame Fast | 10 / sec | 15 / sec | 1.5× | 120 |
| VEO 3.1 Fast Extend Video | 10 / sec | 15 / sec | 1.5× | 120 |
| VEO 3.1 Lite | 5 / sec | 8 / sec | 1.6× | 64 |
| VEO 3.1 Fast | 5 / sec | 8 / sec | 1.6× | 64 |
| VEO 3 Fast | 25 / sec | 40 / sec | 1.6× | 320 |
| VEO 3.1 | 20 / sec | 40 / sec | 2× | 320 |
| VEO 3.1 Reference to Video | 20 / sec | 40 / sec | 2× | 320 |
| VEO First Last Frame | 20 / sec | 40 / sec | 2× | 320 |
| VEO 3.1 Extend Video | 20 / sec | 40 / sec | 2× | 320 |
Every one of these models sells fixed clip durations, so the toggle — not the length — is the lever you actually operate.
Multiplicative sound versus additive sound
The same brief — a clip that makes noise — costed two ways.
| Route | How it bills | What length does to it |
|---|---|---|
| Native audio on the video model | Raises the per-second rate for the whole clip | The premium grows with every second |
| Generated voiceover, attached | Per 1,000 characters of script at 12 credits, plus a flat attach fee | The attach fee is flat regardless of length |
| Generated music bed, attached | Per track generated, plus the same flat attach fee | One track can cover several clips |
Attaching audio copies the video stream without re-encoding it, which is why that step is a flat fee rather than a length-scaled one.
What changes the cost of sound
The audio toggle
2× on the per-second rate on VEO 3.1, applied to every second of the clip.
Which audio-capable model you use
The toggle costs 1.5× on the gentlest model and 2× on the steepest.
Choosing the additive route instead
Replaces a multiplier with a per-script charge and a flat attach fee — usually cheaper on anything long, and the audio is reusable across clips.
Silent-first drafting
Rendering the picture mute while you iterate and once with audio pays the premium once instead of on every attempt.
What the audio rate does not cover
- Sound effects generated as separate items, billed per generation.
- Dubbing an existing video's dialogue into another language — a different job with a flat per-job charge.
- Music licensing. Generated tracks are generated, not licensed from a library.
Silent shots versus scored shots on one plan
A Monthly plan's 580 credits covers 3 silent 8-second shots on VEO 3.1, or 1 with native audio.
Plan sizes and what each grants are on the cost hub.
Models that price audio as a toggle
Every model page shows its own price matrix, its published credit range, and the option table this formula reads from.
VEO First Last Frame Fast
audio_basedGoogle · 40–120 credits
VEO 3.1 Fast Extend Video
audio_based_per_secondGoogle · 70–105 credits
VEO 3.1 Lite
audio_basedGoogle · 20–64 credits
VEO 3.1 Fast
audio_basedGoogle · 20–60 credits
VEO 3 Fast
audio_based_per_secondGoogle · 100–320 credits
VEO 3.1
audio_basedGoogle · 80–320 credits
VEO 3.1 Reference to Video
audio_basedGoogle · 160–320 credits
VEO First Last Frame
audio_basedGoogle · 80–320 credits
VEO 3.1 Extend Video
audio_based_per_secondGoogle · 140–280 credits
Frequently asked questions
Is native audio a surcharge on top of the video price?+
No — it replaces the per-second rate. On VEO 3.1 silent seconds bill at 20 credits and audio seconds at 40; there is no separate line item.
Is it cheaper to add a voiceover instead?+
Usually, on anything but the shortest clips. A voiceover is billed at 12 credits per 1,000 characters and the step that lays it onto the video is a flat fee that does not grow with duration.
Can I turn audio off to iterate and on for the final render?+
Yes, and it is the obvious saving — every silent draft is 160 credits instead of 320 on VEO 3.1.
Do all video models charge for audio this way?+
No. 9 models expose audio as a priced toggle; the rest are silent by design and rely on the additive route.
Does adding music to a finished video cost more for a longer video?+
No. Attaching audio is a flat credit fee regardless of the video's length, because the picture is copied rather than re-encoded.
Different job, different arithmetic
These are not variations on the formula above — each one meters something else entirely.
What does exporting in 4K instead of 1080p cost?
credits = rate_per_second(resolution) × secondsIt switches the per-second rate by resolution band, and the premium differs by model.
What does an AI voiceover cost for my script?
credits = ceil( characters ÷ 1,000 × 12 )It meters the characters you type, not the seconds you get back.
What does a finished 30-second AI ad cost end to end?
credits = (image_price × shots) + (video_rate × seconds) + ceil(chars ÷ 1,000 × 12) + (lipsync_rate × seconds) + exportIt sums four unrelated meters, so no single rate predicts the total.
Which model should I actually pick?
This page prices the job. The buyer's guides rank the models, with the sort criterion stated on every one.
Best AI model with native audio
Filtered to models with an audio-related category or feature tag, sorted by best leaderboard position (unranked models after, cheapest complete job first).
Best premium AI video model
Filtered to video models flagged as premium, sorted by the credits one complete job costs, ascending.
Jobs billed this way
Further reading
See the price before you spend it
Versely quotes the exact credit cost of every generation before it runs, and the agent will estimate a whole batch on request. The all-in-one AI studio for creators. 60+ models for video, image, voice, music and lipsync in a single app.