How to add subtitles to a YouTube video
Make the SRT yourself, upload it in Studio, and replace the auto-captions.
YouTube will caption your video for free, and for most channels that is the wrong choice. Its automatic captions have no punctuation, guess badly at names and jargon, and are marked as automatic in the transcript — which matters because that text is also what the search index reads. Uploading your own subtitle file replaces them entirely, and takes about as long as watching the video once.
Open the subtitle editor → Generates the SRT on your machine. Nothing is uploaded until you upload it to YouTube yourself.- 100% freeNo account, no minute quota, no paid tier.
- Nothing is uploadedYour video is read on your device and never reaches a server.
- No catch on the outputNo watermark, no length cap, no locked export formats.
- Updated in the openEvery fix is written down on the changelog page.
Make the subtitle file first
Open the editor on the home page and drop in the same video file you uploaded to YouTube. Speech recognition runs on your own machine and gives you a full subtitle track in a few minutes. Play it back once and fix the things a model cannot know: your own name, the channel name, product names, anything spelled in an unusual way. Those are also exactly the words people search for, so they are worth the two minutes.
Export as SRT. YouTube also accepts VTT, SBV and a few others, but SRT is the format every other platform takes as well, so one file covers you if the video ends up on LinkedIn or a website later.
Upload it in YouTube Studio
In Studio, open Subtitles in the left sidebar, pick the video, then choose the language and click ADD next to it. Select Upload file, choose With timing, and pick your SRT. YouTube shows you the lines against the video so you can check a few before publishing.
If the video already has automatic captions in that language, your uploaded file takes over as the published version — you do not have to delete the automatic one first, though you can, and doing so avoids confusion later if you come back to edit.
The three things that go wrong
The language you pick at upload has to match the language in the file. Uploading an English SRT under a Spanish track produces captions that display but are labelled wrong, which quietly breaks both accessibility and search.
Timings drift if you edited the video after transcribing it. Always caption the final cut. If you have already published and then trimmed the intro, the whole track will be early by the length of the trim — one shift in the editor fixes it rather than redoing the transcription.
Lines that are too long get cut off on phones. YouTube's player wraps at roughly 40 characters, so a 70-character line becomes three cramped rows over the picture. The editor flags lines that are too wide and the auto-format button re-wraps the whole track in one click.
Why not just use the automatic captions
They are genuinely useful as a fallback and they are getting better every year. But they are still produced without punctuation, which makes a paragraph of speech read as one unbroken run, and they still fail on the specific vocabulary that makes your video yours. For a channel that is trying to be found, the transcript is content, and content you did not check is content you are guessing about.
There is also a practical argument: once you have an SRT you own it. You can upload the same file to Vimeo, attach it to a LinkedIn post, ship it next to an MP4 on your own site, or hand it to a translator. Auto-captions live inside YouTube and stay there.
Frequently asked questions
Does uploading my own SRT remove the automatic captions?
Your uploaded track becomes the published one for that language. The automatic version stops being shown. You can also delete it outright in Studio if you want the list to be unambiguous.
SRT or VTT for YouTube?
Either works. SRT is the safer default because every other platform accepts it too, so the same file works everywhere.
Will subtitles help my video get found?
The subtitle text is indexed, so words that only appear in the spoken audio become searchable. That is a real effect, but it is a supporting one — accurate names and terms matter more than volume of text.
Can I add subtitles to someone else's video?
No. You need to be able to upload to that channel. If you only have the video file, you can still build the subtitle file here and send it to whoever owns the channel.