# AI Caption Generator > An AI caption generator listens to the speech in your video, writes it out as captions timed to the words and draws them onto the picture. Kenerate's version burns the captions into one MP4 in any of 10 styles, from plain white text to Rizz's yellow word highlight, for clips up to 4 minutes at 720p or 1080p. URL: https://kenerateai.com/ai-caption-generator Publisher: Kenerate AI (https://kenerateai.com) Last updated: 3 October 2026 ## Key facts - Caption styles: 10 - Word highlight: Glide Pop, Rizz - Spoken languages: Auto-detect + 10 - Clip length: Up to 4 min, 100 MB - Output: MP4, captions burned in - Ready in: About 1–3 min - Simple (Caption style): Any clip up to 4 min → Clean white text with a soft shadow. Interviews, tutorials, the safe default. - Plain (Caption style): Any clip up to 4 min → Clean white text. Minimal captions over clean footage. - Glass (Caption style): Any clip up to 4 min → Words on a frosted glass pill. Bright or busy backgrounds. - Whisper (Caption style): Any clip up to 4 min → Light italic text. Calm, cinematic or reflective clips. - Glide Pop (Caption style): Any clip up to 4 min → Small white words, the spoken one in yellow script. Vlogs and lifestyle Reels. - Fusion (Caption style): Any clip up to 4 min → Short bursts of words, timed to speech. Fast-paced talking clips. - Terminal (Caption style): Any clip up to 4 min → Green monospace text on black. Tech, coding and gaming clips. - Lowkey (Caption style): Any clip up to 4 min → Small, subtle text. Footage where the picture leads. - Rizz (Caption style): Any clip up to 4 min → Heavy white caps, the spoken word in yellow. Hooks, ads and high-energy clips. - Vegas (Caption style): Any clip up to 4 min → Pink neon caps. Nightlife, music and party clips. ## Steps 1. Sign in and open Auto Subtitles — A verified email is needed; new accounts get starter credits to try it. 2. Upload one video — MP4, MOV or WebM, up to 4 minutes and 100 MB, with clear speech. 3. Choose a caption style — Ten previewed tiles; Simple is selected by default. 4. Set position, resolution and language — Top, Middle or Bottom; 720p or 1080p HD; Auto-detect or a pinned spoken language. 5. Generate and compare — After about 1–3 minutes, check Original vs Captioned side by side, then download the MP4. ## In depth ### From sound wave to on-screen words An AI caption generator runs speech recognition on the audio track, turning speech into words with a start and an end time for each. Those timings decide when each caption appears and, in Glide Pop and Rizz, which word is highlighted. The generator then draws the words onto the frames and encodes a new video, which is why burned-in captions can't be removed afterwards [1]. ### Captions or subtitles? The difference that matters Strictly, captions also describe non-speech sounds such as music or a door slamming, while subtitles carry the dialogue [1]. AI caption generators, Kenerate's included, transcribe speech only. If you need full captions for deaf or hard-of-hearing viewers, with sound descriptions and speaker labels, finish them in a tool that lets you edit the text. ### Four families of caption styles Pick the family first, then the style; position and shadow work the same for all ten. - Clean: Simple, Plain, Lowkey and Fusion — words with no decoration. - Framed: Glass (a frosted pill) and Terminal (green monospace on black). - Highlighted: Glide Pop and Rizz light up the word being spoken. - Expressive: Whisper (light italic) and Vegas (pink neon caps). ### What this caption generator doesn't do Knowing the limits saves you a wasted run. - No caption text or timing editor. - No SRT or VTT file: captions are burned in only. - No translation: dub the video first, then caption it. - No captions for clips without speech. - No Hindi yet: Auto-detect plus 10 spoken-language options. - Clips over 4 minutes or 100 MB need trimming first. References: [1] Subtitles — Wikipedia: https://en.wikipedia.org/wiki/Subtitles [2] YouTube Help — Add subtitles and captions, checked 3 October 2026: https://support.google.com/youtube/answer/2734796 [3] Captions — AI video caption generator, checked 3 October 2026: https://captions.ai/features/add-captions-to-videos ## FAQ Q: Is there a free AI caption generator? A: Kenerate's is not free, but you can try it without paying: new accounts get starter credits to try it, and no subscription is required. After that, Auto Subtitles is priced by clip length in tiers up to 4 minutes, and 1080p costs more than 720p. Failed runs are refunded automatically, and the captioned video has no watermark. Q: How accurate are AI captions? A: Accuracy depends mostly on the audio: one clear speaker, quiet background music and a pinned spoken language give the cleanest captions. Kenerate's captions can't be edited after they are generated, so if a word comes out wrong, run the clip again with the language pinned or with cleaner audio. Heavy accents, crosstalk and loud music cause most mistakes. Q: Which caption style should I use? A: Use Simple or Plain for interviews and tutorials, Rizz or Glide Pop when you want the spoken word highlighted, Glass for bright and busy backgrounds, and Whisper or Lowkey for cinematic footage. Terminal suits tech content and Vegas suits nightlife and music. All ten styles can be placed top, middle or bottom, with four levels of text shadow. Q: Can I edit the words or timing of the captions? A: No. Kenerate's caption generator writes and times the captions automatically and burns them straight into the video, with no text or timing editor. If you need to correct words by hand, choose a tool with a caption editor, such as those in the comparison above. Here, the best fix is cleaner audio and a pinned spoken language before you run it. Q: Does it work on videos without speech? A: No. The captions are written from what is said, so the tool can't caption a silent clip or one with only music and ambience. Add titles to those in a regular video editor instead. When a clip mixes speech and music, keep the voice clearly louder than the music, because the transcript is only as clean as the voice in the audio track. Q: Can captions be in a different language from the speech? A: Not with the caption generator alone: it captions the language that is spoken and doesn't translate. To put Spanish captions on an English video, first dub the video into Spanish with Kenerate's AI dubbing, which has 33 target languages, then caption the dubbed version. This works for any dub language that Auto Subtitles supports, such as French, German, Japanese or Portuguese. Q: What do I get back? A: One MP4 with the captions burned into the picture, at 720p or 1080p HD, with no watermark. The tool shows Original and Captioned side by side so you can check the result before downloading. Because the captions are part of the image, they show on every platform, but viewers can't switch them off and there is no separate subtitle file. ## Related pages - Add subtitles to video: https://kenerateai.com/add-subtitles-to-video - TikTok captions: https://kenerateai.com/tiktok-captions - Auto subtitle generator: https://kenerateai.com/auto-subtitle-generator - AI video translator: https://kenerateai.com/ai-video-translator-and-dubbing - AI video editor: https://kenerateai.com/ai-video-editor ## Sources - Kenerate Auto Subtitles (tool): https://kenerateai.com/app/tool/subtitles - Captions — AI video caption generator, checked 3 October 2026: https://captions.ai/features/add-captions-to-videos - OpusClip — AI caption generator, checked 3 October 2026: https://www.opus.pro/tools/ai-caption-generator - VEED — Auto subtitle generator, checked 3 October 2026: https://www.veed.io/tools/auto-subtitle-generator-online - Subtitles — Wikipedia: https://en.wikipedia.org/wiki/Subtitles - YouTube Help — Add subtitles and captions, checked 3 October 2026: https://support.google.com/youtube/answer/2734796