Local-first
Auto caption on your device—video stays private by default
Captions AI · free auto caption generator
Free auto caption generator for your videos in seconds
AutoCaption is an AI subtitle generator that adds captions for video on your device—auto caption, style, and export ready-to-post clips for TikTok, Reels, and Shorts.
Private on-device transcriptionFree auto caption modeExport MP4 · SRT · VTT
Free to start
No credit card required for the free auto caption generator
Export-ready
Burned-in video or SRT/VTT for every platform
Auto caption
Add captions for video in your browser
Upload a clip, run the auto caption generator locally, then fine-tune styles and timing below.
Try it freeTURN YOUR IDEAS INTO REAL RESULTS
Before
Drag to compare captions on vs off
Features
Everything you need from an auto caption & subtitle generator.
Use captions AI to generate, edit, and style captions for video—then export faster without uploading to our servers.
Caption styles that keep people watching
Dynamic fonts, colors, outlines, and active-word emphasis built for short-form captions for video.
TURN YOUR IDEAS INTO RESULTS
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Private local auto caption
Your video stays on this device. Free local recognition with optional high-quality cloud mode.
0 uploads · on-device
AI subtitle generator with timing control
Fine-tune every cue on a simple timeline—split, merge, and nudge wording with word-level control.
Export and publish faster
Burn captions into MP4/WebM or download SRT/VTT—ready for TikTok, Reels, and Shorts.
MP4SRTVTTWebM
Export
Multiple languages
Transcribe English and more spoken languages, then style captions for every platform.
EN中文ESFRJAKODEPT
Made for creators
Word-level cues, reusable style presets, and a browser auto caption workflow from the first upload.
Word-level cues
Createviralcaptionsin seconds
How it works
Create auto captions in 3 simple steps
From upload to export in minutes—no editing experience needed.
- 1
Upload your video
Drag and drop or select any MP4, MOV, WebM, or M4V file. Local mode supports clips up to 30 minutes.
- 2
Customize your captions
Run auto caption on-device, then adjust fonts, colors, active-word effects, and timing in the timeline.
- 3
Export & publish
Download a captioned video or subtitle file and post to TikTok, Reels, or Shorts.
No credit card required
Why captions AI
Manual captioning is too slow for short-form video
Open a subtitle tool, type or paste a transcript, sync timing word by word, export an SRT, re-import, then fix formatting for mobile. An auto caption generator collapses that grind into upload → edit → export.
- 85% of social video is watched with sound off—captions for video carry your message.
- Word-level captions AI helps viewers stay past the first few seconds on TikTok, Reels, and Shorts.
- A local AI subtitle generator keeps drafts private while you still get editable, styled captions.
Who it's for
Built for creators who post captions for video daily
If you spend more time syncing subtitles than shooting, AutoCaption is the faster auto caption workflow.
TikTok creators
Use an auto caption generator for vertical 9:16 clips with word-level emphasis that holds attention.
Instagram Reels
Add captions for video so mute scrollers still catch your hook, CTA, and product story.
YouTube Shorts & long-form
Generate captions, then export burned-in video or SRT/VTT for Shorts and longer uploads.
Marketers & educators
Ship demos, ads, and lessons with a consistent AI subtitle generator look across every cut.
Platforms
One auto caption workflow for every platform
Style once, then export captions for video in the aspect ratio you need—TikTok, Reels, Shorts, or landscape.
TikTok
9:16
Vertical auto captions optimized for mobile feeds.
Instagram Reels
9:16
Captions AI that stays readable over UI chrome.
YouTube Shorts
9:16
Fast subtitle generator export for short-form discovery.
YouTube / LinkedIn
16:9 · 1:1
Landscape or square captions for video when you need them.
Guide
What is an auto caption generator?
An auto caption generator (also called captions AI or an AI subtitle generator) listens to your video audio, creates timed text, and overlays styled captions for video. AutoCaption at getautocaption.com does this in the browser with a free local-first mode—so you can auto caption, edit timing, and export without sending the file to our servers by default.
Auto caption vs subtitle generator
Creators often search both terms. Auto caption usually means burned-in, social-ready text on the picture. A subtitle generator may also export SRT/VTT for players and accessibility. AutoCaption supports both: style on-screen captions AI and download subtitle files when you need them.
How to add captions for video in minutes
Upload MP4/MOV/WebM, pick the spoken language, run local transcription, fix any words on the timeline, choose fonts and active-word effects, then export MP4/WebM or SRT/VTT. That is the full captions for video loop—no CapCut timeline marathon required.
Why choose a local AI subtitle generator
Cloud tools are convenient, but drafts, unreleased product videos, and client footage often should stay on-device. AutoCaption’s free auto caption mode keeps processing in your browser, with optional high-quality cloud transcription when you want it.
Caption tools
Every caption tool you need
Keyword-focused entry points for auto caption, subtitle generator, and captions AI use cases—jump into the free editor anytime.
AI Caption Generator
Auto-transcribe and style captions for any video with captions AI.
Auto Caption Generator
Free auto caption on your device—edit timing, then export ready-to-post video.
Subtitle Generator
Build burned-in subtitles or download SRT/VTT from the same project.
AI Subtitle Generator
Word-level AI subtitle generator with fonts, colors, and active-word effects.
Captions for Video
Step-by-step captions for video: upload, auto caption, style, and publish.
Captions AI for TikTok & Reels
Vertical-ready captions AI for 9:16 short-form feeds.
FAQ
Frequently asked questions
Everything you need to know about AutoCaption—the free auto caption generator at getautocaption.com.
What is AutoCaption?
AutoCaption is a free auto caption generator and AI subtitle generator. Upload a clip, transcribe locally (or use high-quality mode), style captions for video, and export a ready-to-post file for TikTok, Reels, Shorts, or YouTube.
What video formats are supported?
We support major formats including MP4, MOV, WebM, and M4V. Local transcription currently supports videos up to 30 minutes.
How many languages are supported?
Local transcription covers English and several other spoken languages (including Chinese, Spanish, French, German, Portuguese, Japanese, and Korean), plus auto-detect. High Quality mode in Transcript Studio can cover broader language needs.
Can I customize the caption style?
Yes—you can change fonts (including uploads), colors, outlines, background opacity, position, uppercase, and active-word effects like color, highlight pill, underline, and fill.
Does my video leave my device?
In free local mode, transcription and export run in your browser—your video stays on this device. High Quality mode uses Transcript Studio when you choose it.
Is there a free plan?
Yes. Local auto caption is free to start and does not require a credit card. Optional cloud features may use credits when you sign in.
Can I use captions for multiple platforms?
Absolutely. Export a burned-in video or SRT/VTT and use the canvas aspect ratio that fits TikTok, Instagram Reels, YouTube Shorts, or landscape uploads.
What is an AI caption generator?
An AI caption generator (captions AI) automatically transcribes speech and creates timed captions for video. AutoCaption is also an auto caption generator and AI subtitle generator: it styles on-screen text and can export burned-in video or SRT/VTT.
How long does auto caption processing take?
Local auto caption speed depends on your device, clip length, and whether WebGPU is available. Short clips often finish in about a minute; longer videos take longer. Keep the tab open while transcription runs.
More tools
Every creator tool you need
Purpose-built pages for compression, audio, cleanup, and more.
Video Compressor
Shrink MP4 and MOV files locally with quality or target-size controls.
Audio Extractor
Pull clean audio tracks from video without leaving the browser.
Extract Music from Video
Isolate music beds from clips for reuse in new edits.
AI Video Upscaler
Upscale short clips for sharper social posts.
Remove Background Music
Reduce BGM so speech and captions stay clear.
Metadata Cleaner
Strip identifying metadata before you share a file.
Ready for better captions for video?
AutoCaption helps creators turn any clip into engaging auto captions in minutes—privately on your device at getautocaption.com.
Try it free