Closed Caption Generator
Free Online Tool
Closed captions and open captions are often confused, but they serve different purposes. Closed captions are delivered as a separate file — SRT or VTT — that the viewer can toggle on or off depending on the platform. Open captions are burned directly into the video frame, always visible regardless of whether the player supports caption tracks. AudioSRT generates both from the same transcript.
For educators creating course content, communications teams publishing to corporate intranets, or anyone producing public-facing video, closed captions are a core accessibility requirement under WCAG 2.1 and ADA guidelines. Generating them accurately — and reviewing them before publishing — is what AudioSRT is designed for. Export your SRT or VTT file, upload it alongside your video, and your content meets the baseline requirement.
Generate closed captions →How it works
Upload your video or audio
Load any video or audio format. The file is processed entirely in your browser — no upload to a server, which matters when you're working with internal or unpublished content.
Transcribe and time the captions
Whisper produces word-level timestamps for precise caption timing. Review the transcript and correct any errors before you publish — accuracy matters more for accessibility captions than for internal notes.
Export closed or open captions
Choose SRT or VTT for platforms that support caption track upload (YouTube, Vimeo, LMS platforms). Or export a burned-in MP4 for platforms that don't — social media, direct file distribution, embedded players.
What's included
Accessibility compliance support
Generate the SRT or VTT files needed to meet WCAG 2.1 Level AA and ADA Section 508 captioning requirements for publicly accessible educational and government video content.
Closed captions: SRT and VTT
Export standard caption files compatible with YouTube, Vimeo, Canvas, Brightcove, Panopto, and most LMS and video hosting platforms that accept caption track uploads.
Open captions: burned-in video
For platforms with no caption upload support — social video, standalone MP4 files, digital signage — export a finished video with captions permanently embedded in the frame.
Review before publishing
Edit the transcript for accuracy before export. For accessibility use, caption quality matters — inaccurate auto-generated captions that aren't reviewed don't satisfy compliance requirements.
Generate closed captions now
Free to start. Video captions on the Starter plan — 14-day trial included.
Start for free →