100% Client-Side Processing

AI Captions That Look as Good as Your Content.

Generate beautiful animated captions locally in your browser. No server uploads, no data leak risks, and free to use.

No sign up No server uploads Free to use
99%
Accuracy Rate
10+
Caption Templates
0
Server Uploads
100%
Browser Processed

Everything creators need.
Nothing extra.

A professional subtitle workflow engineered directly into your web browser. No cloud limits, no delays.

Local Processing

Your video never uploads to any server. AI transcription runs directly inside your browser tab using WebAssembly.

Privacy First

Complete data isolation. Ideal for corporate videos, pre-released content, and privacy-conscious digital creators.

Live Style Preview

See your captions render in real time on the video as you adjust fonts, colors, and animations. What you preview is exactly what exports.

Zero Wait Time

Skip queue times. Traditional SaaS renders force you to wait in line. Kaptions utilizes your GPU locally for instant renders.

One-Click Export

Burn your styled captions straight into the video and download an HD MP4 in a single click — no watermarks, no accounts.

Template Presets

Apply 10+ custom caption presets instantly. Get viral text styles, custom shadow alignments, and glowing fonts in one click.

Subtitles in Seconds

Four simple steps to auto-generate fully custom animated subtitles.

1

Upload

Select your MP4 or MOV file from your hard drive securely.

2

Generate

AI local voice recognition drafts timing metadata instantly.

3

Customize

Select template colors, text outlines, or change fonts.

4

Export

Burn captions and export HD video files directly to your machine.

Your videos stay on your computer.

Unlike cloud-based editors that upload gigabytes of personal footage to remote clouds, Kaptions processes everything client-side. Speed and absolute privacy by design.

No Server Transfers

Video decoding, transcribing, styling, and final MP4 encoding run inside memory local to your browser.

Zero Account Overhead

Get started immediately without typing emails or entering credit cards. Open the page and edit.

Compliance Ready

Enterprise and corporate environments can safely handle NDAs and secure marketing assets offline.

https://Kaptions.app
Local Sandbox

Processing Offline

Whisper transcription running via local WebAssembly. Safe & Private.

Designed for modern creators.

Hover any preset to see the real animation — these previews run the exact renderer that powers the app. Explore all 10+ styles →

Accurate transcription, on your device.

English speech-to-text runs entirely in your browser with OpenAI's Whisper model — no uploads, no queues, no API bills.

🇺🇸 English
🔒 100% On-Device
Word-Timed Captions
🎬 HD MP4 Export
🌐 More languages soon

Why creators switch.

How Kaptions compares against traditional cloud-based video captioning applications.

Feature Kaptions Traditional Apps
Browser-based processing
Videos never leave device
Zero upload wait time
Real-time caption preview
10+ modern templates
Live style preview
Subscription required

Frequently asked questions

Everything you need to know about generating captions with Kaptions.

Is Kaptions really free to use?

Yes. Kaptions is completely free — no account, no credit card, and no watermarks on your exported videos. Everything runs in your browser, so there are no server costs to pass on to you.

Are my videos uploaded to a server?

No. Transcription, styling, and final video encoding all happen locally in your browser using WebAssembly. Your footage never leaves your device, which makes Kaptions ideal for private, corporate, or unreleased content.

What languages are supported?

Kaptions currently transcribes English audio with word-level timing using OpenAI's Whisper model, running entirely on-device. Support for additional languages is on the way.

How many caption styles can I choose from?

There are 10+ animated caption presets — including Attractive, Highlight, Motion Stack, Active, and Impact — and each one is fully customizable. You can adjust fonts, colors, outlines, shadows, positioning, and animations, then preview the result live before exporting.

What video formats can I upload and export?

Upload common formats like MP4 and MOV directly from your device. When you're done, Kaptions burns the captions into the video and exports a high-quality MP4 in a single click.

Do I need a powerful computer?

Kaptions runs on any modern browser and uses your device's hardware for processing. A recent laptop or desktop handles it comfortably — and because there's no upload queue, you skip the wait times of cloud-based tools.