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Knockout API

Freemium#3 of 30 in Green Screen SoftwareVideo Background Removal Software AI Background Removers AI Video Background Removers +1 more

Knockout API: A developer-focused background API with alpha video output and self-hosting. Ranked #3 of 30 in Green Screen Software by our editors (9.2/10); pricing: Free plan; best for developers needing flexible alpha-video processing.

9.2/10Editor score

Visit Knockout API

Knockout API9.2 Visit Knockout API

At a glance

Editor score
9.2 / 10
Pricing
Free plan
Best for
Developers needing flexible alpha-video processing
Free plan
Yes
Paid from
$10/mo
Facts checked
20 Sep 2026

Where it wins
- Real alpha-channel output with ProRes 4444 and WebM export
- Background replacement, blur compositing, and image cutouts
- Open-source API with REST, SDK, CLI, and self-hosting options
Where it doesn't
- Video processing is limited to 1080p and 30-second clips
- Video background removal is available only on paid tiers
- Free plan is limited to 30 images per month

Our verdict on Knockout API

Knockout API is a hosted, open-source background-processing API for developers and product teams. It handles video background removal with real alpha-channel output, image cutouts, background replacement, blur compositing, portrait restoration, headshot processing, and layered exports. The API is accessed over REST, with Node, React, Python, CLI, and other SDK options, and it is available through web, API, and self-hosted deployments. Supported video inputs include MP4, MOV, AVI, WebM, and MKV.

The published plans create a clear progression from experimentation to higher-volume use. Free includes 30 images every month, background removal endpoints, no card requirement, and community support. Pay-as-you-go starts at $0.02 per image monthly and adds all endpoints, metered usage, and email support. Knockout Plus costs $10 per month and includes 250 images, layered PSD export, saved presets, custom watermarks, and a lower listed video-processing rate. Volume offers negotiated per-image pricing, an optional negotiated SLA, Slack support, and a usage dashboard. Video processing is reserved for paid tiers.

Its standout capability is transparent video output: asynchronous processing can produce ProRes 4444, WebM with alpha, or opaque MP4 output. Image workflows support PNG or WebP output and batch processing of up to 10 images. The main boundary is scope: clips are limited to 30 seconds, and frames above 1080p are downscaled. Knockout API fits teams that want programmable background processing, flexible deployment, and alpha-video export. Teams needing longer clips or higher video resolution should consider an alternative.

Your product? Our editors can test Knockout API in depth and publish a review, labelled as paid · from $149/mo →

Knockout API pricing

Plans Free planFreemium A usable free plan; paid tiers unlock the limits above. Prices checked 20 Sep 2026.

See plans on useknockout.com

All 4 Knockout API plans and prices →

Knockout API fact sheet

Free plan	Yes
Paid from	$10/mo
Input media	Not verified
AI background removal	Not verified
Max export resolution	Not verified
Max video length	Not verified
Transparent export	Not verified
Batch processing	Yes
API access	Not verified
Deployment	Cloud, Self-hosted
Platforms	Web
Compliance & security	2FA
Support	Email, Community, Docs, Live chat
Built for	Small business, Mid-market, Enterprise (editorial estimate)
Pricing	Free plan (source)
Website	useknockout.com
Facts checked	20 Sep 2026

Alternatives to Knockout API

See all Knockout API alternatives →

Knockout API vs the competition

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Also Ranked In

Knockout API is ranked in 5 of our directories.

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The editor score above is our own research. What this page doesn't have yet is a reader's view — what you used Knockout API for, what worked and what didn't. No stars are seeded and no review is paid for; an editor reads every one before it appears.

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Featured on iTechGuides

Knockout API is listed in our Green Screen Software directory. Add the badge to your site — it links back to this page.

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Reviewed by iTechGuides Editors · Editorial team · Updated Oct 2026

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Last updated 7 Oct 2026 · How we research and update