Subtitle Generator — Auto-Generate Subtitles from Video or Audio (Free)
Upload any video or audio file. Get accurate subtitles in 100+ languages with word-level timestamps. Download as SRT, VTT, or TXT — or burn in with custom styling. 30 minutes free, no credit card.
30 min free · SRT / VTT / TXT / burn-in · 100+ languages · Whisper Large-v3
TL;DR
VexaScribe's subtitle generator turns any audio or video into SRT, VTT, TXT, or burned-in subtitles using Whisper Large-v3 in 100+ languages. 30 minutes free, no credit card. Paid plans from $2/mo (200 min) to $20/mo (6,000 min) — roughly $0.60 to $0.20 per hour of media.
Subtitle vs caption — which do you actually want?
Most tools use the terms interchangeably. The technical difference matters for accessibility compliance.
| Format | What it contains | Use when |
|---|---|---|
| Subtitles | Dialogue only — for viewers who can hear the audio | Language translation, sound-off social feeds |
| Closed captions | Dialogue + [music], [applause], speaker labels | ADA / WCAG accessibility compliance |
For the full breakdown of ADA, WCAG 2.1 SC 1.2.2/1.2.4, and DOJ Title II 2024, see What is closed captioning?
How the subtitle generator works
Upload
Drag-and-drop MP3, WAV, M4A, FLAC, MP4, MOV, MKV, or WebM. Files up to 5GB.
Generate
Whisper Large-v3 transcribes and produces word-level timestamps in 100+ languages. Processing takes 20–40% of the media duration.
Download or burn in
Export SRT, VTT, or TXT — or burn subtitles into the video with your font, size, color, and position.
Which format do I need for my platform?
Every platform accepts subtitles differently. Instagram and YouTube Shorts don't support sidecar SRT on native uploads — you have to burn in. Long-form and desktop platforms prefer SRT.
| Platform | Delivery | Notes |
|---|---|---|
| YouTube long-form | SRT | Upload in YouTube Studio → Subtitles. VTT also accepted. |
| YouTube Shorts | Burn-in | Sidecar SRTs are cropped by the vertical UI — burn in for reliability. |
| Instagram Reels | Burn-in | Instagram does not accept SRT upload on Reels (help.instagram.com). Burn in only. |
| TikTok | Burn-in OR SRT base | TikTok caption editor accepts an SRT base; most creators burn in for style control. |
| LinkedIn native video | SRT | Upload SRT in the LinkedIn video composer. |
| Facebook video | SRT | Upload via Creator Studio → Captions. |
| Vimeo | SRT or VTT | Vimeo player supports both; SRT is simplest. |
| Podcast platforms | TXT | Use TXT for show notes and episode transcripts (Apple Podcasts, Spotify). |
| Corporate LMS | SRT or VTT | Most LMS platforms (Cornerstone, Docebo, Canvas) accept both. VTT if you need positioning. |
For a deeper dive on the SRT format, see what is an SRT file? For YouTube specifically, YouTube Studio SRT upload is documented at support.google.com/youtube. Already have an SRT and just need to translate it to another language? Use the dedicated subtitle translator — timestamps preserved, 133 target languages.
Customizing burned-in subtitle style
When you burn subtitles into the video, you control every visual attribute. Common presets for short-form:
- • Font: Inter, Roboto, Montserrat, or Impact (broadcast-style). Custom fonts by upload.
- • Size: 24–48pt on a 1080×1920 vertical frame; 32–60pt for aggressive social styles.
- • Color: White text with a black outline, or brand-color solid fill with drop shadow.
- • Position: Bottom third (default), centered, or upper-third to avoid TikTok/Reels UI overlays.
- • Karaoke / word-highlight: Highlight the active word as it's spoken — matches CapCut and VEED style presets.
- • Background: Transparent, solid, or semi-transparent pill behind each cue.
Language coverage and accuracy
We use OpenAI Whisper Large-v3, which covers 100+ languages. Accuracy varies by language and audio quality. The table below shows word error rate (WER) on the model's benchmark set — lower is better.
| Language | Whisper Large-v3 WER |
|---|---|
| English | ~4.2% |
| Spanish | ~4% |
| French | ~4% |
| Italian | ~5% |
| German | ~5% |
| Portuguese | ~5% |
| Dutch | ~6% |
| Polish | ~6% |
| Russian | ~6% |
| Turkish | ~7% |
| Japanese | ~7% |
| Korean | ~7% |
| Ukrainian | ~7% |
| Mandarin | ~8% |
| Arabic | ~8% |
Source: Radford et al., Robust Speech Recognition via Large-Scale Weak Supervision, arXiv:2212.04356, Table 5. WER measured on FLEURS/CommonVoice benchmark subsets. Real-world audio (background noise, heavy accents, technical vocabulary) will show higher WER.
Editing subtitles after generation
Every subtitle project opens in a full editor with the video preview synced to the cues. You can:
- • Fix misheard words with click-to-edit — timestamps update automatically.
- • Merge or split cues at word boundaries for readability.
- • Rename speakers and preserve speaker labels through SRT export.
- • Adjust cue duration to match speaker delivery (dramatic pauses, fast dialogue).
- • Add non-speech notation like [applause] or [music] for accessibility compliance.
- • Re-export as SRT, VTT, TXT, or a re-burned MP4 without regenerating from scratch.
Bulk generation
Upload up to 50 files at once for batch processing on any paid plan. Useful for course creators subtitling a full module, agencies processing a client backlog, or podcasters generating show-note transcripts across an entire season. Each file lands in your library as an independent project with its own editor and export options.
When to hire a human transcriptionist instead
AI subtitle generators land at 92–96% accuracy on clean audio. For contexts where the remaining 4–8% is unacceptable, use a human service:
- • Broadcast television — FCC accuracy standards require near-perfect captions.
- • Legal proceedings — court transcripts and depositions need certified accuracy.
- • Medical dictation — drug names and procedures where a single misheard word has clinical consequences.
- • Named entities under legal review — patents, contracts, regulatory filings.
A common workflow: run AI generation first (fast + cheap), then hand the SRT to a human editor for a review pass. Services like Rev and Happy Scribe offer human review at $1.50–$2.00 per audio minute — see our comparison of subtitle tools for details.
Frequently asked questions
Is your subtitle generator free?
Yes — we give you 30 minutes of subtitle generation free with no credit card required. That's enough for several short-form videos or one podcast episode. After that, paid plans start at $2/month for 200 minutes (Starter), which works out to about $0.60 per hour of video. Plans go up to Studio at $20/month for 6,000 minutes if you're generating subtitles at volume.
How accurate is auto-generated subtitle output?
We use OpenAI's Whisper Large-v3, which reports the following per-language WER (word error rate) on the paper's public benchmarks (arXiv:2212.04356, Table 5): English ~4.2%, Spanish ~4%, German ~5%, French ~4%, Turkish ~7%. That translates to roughly 93–96% accuracy on clean speech. Expect lower accuracy on background music, heavy accents, technical vocabulary, or overlapping speakers. For broadcast, legal, or medical contexts that need 99%+, plan a human review pass or hire a professional transcriptionist.
What languages are supported?
100+ languages, powered by Whisper Large-v3. The generator auto-detects the spoken language, or you can set it manually. Coverage is strongest for English, Spanish, French, German, Portuguese, Italian, Dutch, Russian, Japanese, Korean, Mandarin, and Arabic. Lower-resource languages work but tend to have higher WER.
Can I generate burned-in subtitles or just SRT files?
Both. You can download SRT, VTT, or TXT sidecar files for upload to YouTube, Vimeo, LinkedIn, Facebook Creator Studio, or any LMS. You can also generate burned-in (hardcoded) subtitles with customizable font, size, color, background, and positioning — required for Instagram Reels and TikTok, since neither platform accepts sidecar SRT uploads on native posts.
Can I use this for TikTok / Instagram / YouTube?
Yes, but the delivery format differs per platform. YouTube long-form: upload SRT in Studio. YouTube Shorts, Instagram Reels, and TikTok: use burned-in subtitles (Instagram Reels does not accept SRT upload per help.instagram.com; TikTok has a caption editor that accepts an SRT base). LinkedIn native video and Vimeo: SRT sidecar. Facebook video: SRT via Creator Studio.
What's the difference between a subtitle generator and a caption generator?
In practice most tools use the terms interchangeably. Strictly: subtitles transcribe or translate dialogue for a viewer who can hear the audio; closed captions add non-speech audio cues like [music], [applause], and speaker labels for deaf and hard-of-hearing viewers. If you need ADA/WCAG-compliant closed captions, add the non-speech notation in the built-in editor after generation. See our /what-is-closed-captioning page for the full compliance breakdown.
Can I generate subtitles from an audio file (no video)?
Yes. Upload any audio file (MP3, WAV, M4A, FLAC, OGG, AAC) and we'll generate an SRT or VTT with word-level timestamps. You can then mux the SRT with the audio in your video editor, or use it as a standalone transcript for a podcast episode.
How long does it take?
Typically 20–40% of the media duration. A 10-minute video generates subtitles in roughly 2–4 minutes; a 60-minute podcast in 12–25 minutes. Longer files run in the background — you can close the tab and come back.
What if my video is in multiple languages?
Whisper Large-v3 detects code-switching within a segment, but accuracy drops at each language boundary. If you know the primary language, set it manually rather than relying on auto-detect — this reduces mid-file misdetections. For heavily multilingual content (e.g., bilingual interviews), consider generating subtitles per language segment and merging in the editor.
Comparing tools?
If you're shopping around, we ranked 12 subtitle generators (including ours, honestly at #3) on accuracy, free-tier reality, format support, and per-hour cost.
See the 12-tool ranking →