Subtitles make your video watchable with the sound off, accessible to deaf and hard-of-hearing viewers, and easier to follow for anyone watching in a second language. There are two ways to add subtitles to video: type them yourself, or import a subtitle file you already have. Trimzio supports both, entirely in your browser, and burns the result into the exported file so it plays everywhere. Here is the full workflow.
Burned-in subtitles vs subtitle files
A subtitle file like .srt or .vtt travels alongside your video and can be toggled on and off by the player. Burned-in (open) captions are rendered into the pixels of the video itself. Platforms like YouTube accept subtitle files, but most social feeds, messaging apps, and embedded players do not, which is why burned-in subtitles are the safe default for anything shared outside YouTube. If you publish in several places, the practical combination is both: keep the .srt for platforms that accept one, and export a burned-in version for everywhere else. Trimzio takes either path as input and produces burned-in subtitles on export.
Option 1: import an SRT or VTT file
- Get your subtitle file. You may already have one from a transcription service, YouTube Studio’s caption export, or a colleague. Both .srt and .vtt work.
- Open your video in the editor. The file loads locally; nothing is uploaded, which matters if the footage is private.
- Import the subtitle file. Trimzio reads the timestamps and text, and the captions appear over the preview in sync with the audio.
- Check the sync. Play a few sections. If lines run early or late, adjust their timing so each caption lands with the speech.
- Style once, apply everywhere. Set the font size, color, and position for captions across the video. Bottom-center is the convention; move them up if platform interfaces cover that area.
- Export. The subtitles are baked into the MP4 or WebM file.
Option 2: type subtitles manually
No transcript? Manual captioning is quicker than it sounds for short videos.
- Play the video and pause at the start of the first sentence.
- Add a caption and type what is said. Keep each caption to one or two short lines.
- Set the caption to end where the sentence ends, then move to the next one.
- Repeat to the end, then watch the whole video once to catch typos and timing slips.
A rule of thumb: captions should sit on screen at a comfortable reading pace, around 15 to 20 characters per second. If a caption flashes by, split the sentence in two.
No transcript yet? How to get an SRT file
If typing feels slow and you do not have a transcript, you have free routes to one. If the video is already on YouTube (even unlisted), YouTube Studio generates automatic captions you can correct in its editor and download as an .srt file. Free and freemium transcription tools will also take an audio or video file and hand back an SRT with timestamps. Quality varies with audio clarity, accents, and technical vocabulary, so treat any machine transcript as a first draft.
Whichever route you take, budget a correction pass: fix names, brands, and numbers, break overly long lines in two, and check that punctuation matches how sentences are actually spoken. Then import the corrected file into Trimzio, where you can still fine-tune individual captions before styling and export. The combination of a machine-generated draft plus five minutes of human cleanup is the best effort-to-quality ratio available right now.
Styling that keeps subtitles readable
- Contrast first. White text with a dark outline or backing bar survives any footage underneath.
- Do not go tiny. Most subtitle complaints are about size. Err larger, especially for vertical video watched on phones.
- Stay consistent. One style for the whole video. Style changes mid-video read as mistakes.
- Respect line length. Around 40 characters per line is a comfortable ceiling; longer lines force the eye to travel and fall behind the audio.
- Position for the platform. Bottom-center for YouTube and general sharing; higher placement for vertical feeds where interface elements cover the bottom of the frame.
If you are captioning for TikTok, Reels, or Shorts specifically, placement rules differ by platform; see captions for social media videos for a platform-by-platform breakdown.
FAQ
Can viewers turn burned-in subtitles off?
No. They are part of the picture. If you need toggleable subtitles, upload a subtitle file to platforms that support it, and consider exporting a burned-in version for everywhere else.
Does Trimzio auto-generate subtitles?
Trimzio does not transcribe audio for you. It imports .srt and .vtt files and lets you type captions manually, then styles and burns them in. Pairing a free transcription tool’s SRT export with Trimzio works well.
Will my subtitle file leave my computer?
No. Like your video, the subtitle file is processed locally in the browser. More on that in the FAQ.
Make every word land: open Trimzio and add subtitles to your video now, free and in your browser.