Seedream 5.5: ByteDance's image model with 100-round stable editing and native transparent backgrounds

Updated on November 10, 2026

Seedream 5.5 is ByteDance Seed's multimodal image generation and editing model, announced on November 9, 2026. Three headline upgrades define it: iterative editing that holds unedited pixels across up to 100 rounds, native RGBA output with transparent or semi-transparent backgrounds, and sharper realism on skin textures and small dense text. Outside China the model is accessible through Dola and the BytePlus Playground; ByteDance published no official pricing, but Chinese press reports put a 2K square edit at roughly 0.28 yuan on Volcano Engine Ark.

Seedream 5.5 compared with earlier versions

The standout feature of Seedream 5.5 is edit stability over long sessions. In ByteDance's own demo, a single portrait goes through 100 consecutive edits, each round feeding its predecessor's output: clothes, glasses, rings and background objects change while the face, pose and lighting remain consistent. ByteDance describes the result as pixel-level preservation with no color drift.

The model also produces RGBA images with a full or partial alpha channel. A product shot, a character or a set of stickers comes out on a transparent field, ready for compositing without a background-removal pass. Demo assets include a snowy owl with finely separated feathers and stylized lettering rendered over nothing.

Text fidelity rounds out the upgrade. ByteDance reports a severe text-corruption rate of 0.4% and a minor rate of 1.7%, covering Chinese, English and dense small print. On its internal MagicArena platform, evaluated across six professional scenarios, quality and usability scores rose against Seedream 5.0 Pro in every category. No independent leaderboard had confirmed these figures at launch.

Access routes and API pricing

ByteDance's product page links to two entry points outside China: the Dola chat assistant and the BytePlus Playground. Inside China, rollout covers Jimeng, Doubao, Doubao Work and Volcano Engine Ark. Third-party resellers including WaveSpeed, Atlas Cloud and Higgsfield already expose Seedream 5.5 through their own APIs.

No official price table appeared on ByteDance's pages at launch. Chinese outlets Leiphone and IT Home report about 0.28 yuan per 2K square edit on Volcano Engine Ark, less than half the Seedream 5.0 Pro cost, with billing split between input and output images and text tokens free. On Atlas Cloud the listed rate starts at $0.016 per image. These figures may change; always check the platform you plan to use.

Market position and caveats

According to its own MagicArena evaluation, ByteDance claims Seedream 5.5 outperforms GPT Image 2.5 Sunburst and Nano Banana 2.1 on text structure and text-to-image realism. These are vendor-reported numbers, not independent findings, and GPT Image 2.6, released five days earlier, was not included in the published comparison.

The release cadence has been brisk: Seedream 4.5 in December 2025, 5.0 Lite in February 2026, 5.0 Pro in July 2026, and 5.5 in November 2026, roughly 124 days after the Pro. A Pro variant of the 5.5 series is planned but undated. For teams already calling the Seedream API, switching should amount to a model-name change and a test run, assuming the request format stays close to 5.0 (likely but unconfirmed).

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