How to convert MP4 to SRT

MP4 usually wraps H.264 video with AAC audio. Transcription cares about the audio track, not the resolution. A sharp 4K file with muddy sound still produces muddy text.

You will walk through checks anyone on a small team can run: confirm audio exists, upload sensibly, review cues against what you hear, then store the SRT where your editor can find it. You will also see when extracting audio first saves time and when keeping the MP4 whole is simpler.

Use our free converter when you want the MP4 handled in one step: upload, wait, download SRT. You can still extract audio locally if bandwidth is tight, but the same review rules apply either way.

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Rather do it than read about it? Upload an audio or video file and get a timed .srt back.No signup, no payment, up to 100 MB per file.

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Step-by-step guide

Step 1: Confirm you actually have usable audio

Open the MP4 in any player. Unmute. If the track is silent, transcription has nothing to grab. If audio lives on a secondary track, export a mixdown before you upload.

Step 2: Upload the MP4 or extract audio first

Uploading the MP4 is fine when bandwidth allows. If upload speed hurts, strip audio to WAV in your NLE and upload that instead. Keep one reference MP4 for sync checks either way.

Step 3: Wait for processing and open results calmly

Long files take longer. When the job completes, scan the transcript for obvious nonsense in the first minute. If the first minute looks sane, continue. If not, fix language or source audio before you edit hundreds of cues.

Step 4: Compare cues to the soundtrack

Use the preview player if your session still has the source. Hearing while reading catches early drops and late cues faster than scanning text alone.

Step 5: Fix priority errors before cosmetic ones

Names, numbers, and safety-related words come first. Then tighten phrasing. Then worry about comma debates.

Step 6: Save the SRT next to your deliverables

Store projectname.srt with the final MP4 and a textless master if you have one. Future you will not remember which random download folder held the captions.

Step 7: Re-run only when the edit changes dialogue

If you re-cut picture but keep the same spoken words, you might patch cues. If dialogue changes heavily, regenerate instead of hand-fixing hundreds of lines.

Tips for better subtitles

Screen recordings with tiny system audio need level boosts before upload.
If you film interviews with dual mics, sync audio in the NLE first so captions match what viewers hear.
For heavy music beds, expect more manual cleanup or a dialogue stem.
Keep bitrate reasonable on export. Extreme compression adds swishy artifacts that confuse models.
If you localize, duplicate the project folder per language instead of mixing tracks.
Always preview captions on a phone once before wide release.

Common mistakes

Assuming HD video fixes bad audio Pixels do not help speech recognition. Fix the mix.
Uploading a proxy with muted dialogue Editors sometimes swap proxies. Confirm the track you send is the one viewers hear.
Letting overlaps slide Overlapping cues flicker on some players. Tighten ends and starts.
Forgetting to download before the session ends Download early. Keep your own archive.

FAQ

Can I use the SRT in Premiere or Resolve?

Yes, both read SRT directly: in Premiere import it into a captions track, in Resolve bring it onto the subtitle track in the edit page. Timings live inside the file, so the only thing to check is that you import it against the same cut you transcribed.

Does video quality affect the subtitles?

No. Only the audio track is used, so a 4K master and a compressed screen recording of the same interview give the same result. When captions come out poor, the fix is in the sound, not in the picture.

My MP4 is larger than 100 MB. What now?

Export the audio on its own as MP3 or M4A and upload that instead. A 45 minute conversation is a few hundred megabytes as video and roughly 40 MB as audio, so one export usually solves it.

Conclusion

MP4 is just a container. Success still comes from clean dialogue, careful review, and disciplined file naming. Treat the SRT like part of your delivery package, not a side effect.

Upload your MP4 when you want a timed draft, then finish the job in the editor you already use.

Now on your own file

The quickest way to finish this guide is to walk through these steps on your own recording: upload it, correct any line against the audio, download the .srt.Your upload and the subtitles are deleted automatically about an hour after the conversion.