Omni 1.1 Flash vs Seedance 2.5: The 2026 AI Video Comparison

Why This Comparison Matters

Frame quality is the wrong yardstick here. Neither vendor publishes comparable quality metrics, and any “looks better to me” take you read is one person's screenshot. What is comparable is product philosophy. Google announced Omni 1.1 Flash on August 27, 2026 with a pitch about control: extend scenes conversationally, draft cheap at 360p, pay only when you upscale. ByteDance's Seed team introduced Seedance 2.5 with a pitch about scale: one pass, 30 seconds, audio included, up to 30 images and 20 clips as reference material.

One model treats video generation as a conversation you iterate on. The other treats it as a one-take film set. Which one fits your workflow depends on specifics (duration, audio, resolution, inputs, price), so that's exactly what we compare below, with every claim traced to an official source.

The Two Contenders

The lineage detail worth knowing: Seedance 2.5 is not a ground-up rewrite — ByteDance says it was built “on the unified multimodal audio-video joint-generation architecture of Seedance 2.0.” Omni 1.1 Flash, meanwhile, is the first update to Google's Omni Flash line, and its headline gains are incremental and practical: scene extension reads up to 10 seconds of prior context (up from 1 second), and 360p drafts cut cost to roughly a third of 720p.

Specs at a Glance

Every cell below comes from the vendors' own blogs and documentation. Where a company didn't publish a figure, we say so instead of guessing.

Duration & Storytelling

Seedance 2.5 is the clear winner if raw length is what you need. ByteDance doubled the single-pass limit from 15 seconds to 30 seconds, and multi-round extension pushes output to “videos lasting several minutes” — the company frames this as moving “from merely generating a clip to completing a creative work.”

Omni 1.1 Flash plays a different game. The Gemini API docs list output lengths of 3–10 seconds, and the August update improved scene extension: you append 10-second increments and can accumulate up to 40 seconds, with the model reading up to 10 seconds of prior context per extension (the previous version saw just 1 second, which made extended scenes drift). That's a quarter of Seedance's ceiling, but the mechanism, a conversation where each turn grows the clip, is unique, and Google ships it through the new Interactions API so the model remembers the full creative session.

Narrative work longer than a minute belongs on Seedance 2.5 today. Iterative, shot-by-shot work where you renegotiate the content of each clip fits Omni's extension loop better.

Resolution & the Draft-Then-Upscale Workflow

Google is the only one of the two that publishes resolution numbers. Omni 1.1 Flash previews render at 720p at 24FPS, with one-click upscaling to 1080p or 4K. The smarter addition is 360p draft mode: drafts come back up to 60% faster at roughly one-third the cost of 720p (about $0.03 per second), so you can burn through prompt iterations before paying for the good render.

ByteDance has not published a resolution figure for Seedance 2.5, not in the launch blog and not in docs. The company emphasizes instead that 2.5 “optimizes skin, eye, and texture details” and improves lighting and color. Any specific pixel number you see quoted for Seedance 2.5 elsewhere is coming from third parties, not the vendor.

Audio: A Real Split

This is the sharpest dividing line in the whole comparison. Seedance 2.5 generates audio jointly with video in the same 30-second pass (dialogue, effects, music) while keeping audio-visual sync intact, and it preserves multiple characters' voices across edits. That capability is inherited straight from the Seedance 2.0 architecture.

Omni 1.1 Flash does not claim audio generation. Google's video documentation lists its output as video only, and the “native audio” phrasing in Google's stack is reserved for Veo 3.1. If you need sound out of the box, Seedance 2.5 is currently the only option between these two. With Omni, you're dubbing or scoring in a separate step (or reaching for a different Google model entirely).

Reference Inputs

Seedance 2.5 treats references as a first-class feature: up to 30 images, 10 video clips, and 10 audio clips in a single pass, with three dedicated modes: clay render (control layout and composition), motion (transfer movement from a reference clip), and creative (looser style transfer). For storyboarding from existing assets, that's a serious toolkit.

Omni 1.1 Flash accepts multimodal input too (text, images, and as of this release up to 3 seconds of video for editing-style tasks), all inside a 1M-token context window. The emphasis is different. Google talks about “multi-input reasoning” and character consistency across a multi-turn session rather than bulk asset ingestion. Three seconds of reference video versus fifty reference files is a workflow decision, not a footnote.

Editing & Scene Control

Both vendors made editing the centerpiece of their announcements, but they mean opposite things by it.

Omni 1.1 Flash is conversational: you ask for a change in plain language, the model applies it and remembers the session through the Interactions API. It also added first and last frame keyframes, which unlocks camera orbits and seamless loops, on top of the improved scene extension covered above.

Seedance 2.5 is surgical: timestamp-level control over what changes and when, green screen support, camera perspective adjustment, and reference-based edits that preserve multiple characters' appearances and voices. It also works to minimize two classic AI video annoyances: uncontrolled burned-in subtitles and unsolicited background music. If you think in editor terms (EDLs, keyed layers, shot matching), Seedance speaks your language; if you think in director terms (“make the last shot sunset, keep everything else”), Omni does.

Pricing & Availability

Google publishes a full price sheet. On the Gemini API paid tier, Omni 1.1 Flash costs $1.50 per million input tokens and $17.50 per million output video tokens; Google's own math puts effective 720p output around $0.10 per second, with 360p drafts at roughly a third of that. Upscaling to 1080p/4K is billed on top.

ByteDance has published nothing on Seedance 2.5 pricing. Access today is through Jimeng AI and Doubao Pro in supported regions, with API access “coming soon” through BytePlus ModelArk. That “coming soon” matters if you're building a product. Omni 1.1 Flash is generally available right now on the Gemini API, in AI Studio, and on Agent Platform for enterprise, plus Flow and scene extension in the Gemini app for AI Plus/Pro/Ultra subscribers.

One vendor gives you a public API and a public price; the other gives you consumer apps and a promise.

Which Model Should You Pick?

These models optimize for different jobs. Omni 1.1 Flash wins on availability, pricing clarity, drafts, and 4K upscaling; Seedance 2.5 wins on duration, native joint audio, and reference capacity. A pragmatic 2026 stack drafts on Omni's cheap 360p mode, then produces long narrated pieces on Seedance 2.5 where access allows.

FAQ