Verified local conversion

SUB to SRT

Converting a .sub file to .srt extracts the document's content from its office package into a portable form. Free, private, and validated — the file never leaves your browser.

Private for supported formats — processed in your browser

Convert supported files

Runs on your device

Drop SUB files here

Batch files can each use a different output. Nothing uploads for local conversions.

Working inputs include camera RAW, browser-local audio/video, PDF, CBZ/CBR comics, office documents, ebooks, markup, 3D models, structured text, images, and archives.

About converting MicroDVD subtitles to SubRip subtitles

Converting a .sub file to .srt extracts the document's content from its office package into a portable form. A .sub file in the MicroDVD convention is a frame-based subtitle list: every line reads {startFrame}{endFrame}text, with a pipe character separating the lines inside one cue. Because the timing is expressed in frames rather than milliseconds, a MicroDVD file only means anything alongside the frame rate of the video it was timed to.

A .srt file is a SubRip subtitle document: numbered cues with start and end timestamps and plain caption text. It is the most common caption sidecar for video players, editors, and streaming toolchains that need a simple, widely understood text format. For this route the practical draw is universally understood by media players and editors and human-editable in any text editor — balanced against no standard support for advanced styling, voices, or regions, which is worth knowing before you commit a large batch.

Why convert SUB to SRT?

The practical trigger for this conversion is usually a mismatch: with .sub, meaningless without the correct frame rate; the wrong value drifts the whole file. Switching to .srt buys you universally understood by media players and editors, which is why it is the better fit for delivering captions alongside MP4 or MKV downloads. Because the conversion runs locally, trying it costs nothing but a few seconds of compute on your own machine.

SUB vs SRT at a glance

AspectMicroDVD subtitles (.sub)SubRip subtitles (.srt)
Format typeText-based — characters and structure, so there is no visual quality lossText-based — characters and structure, so there is no visual quality loss
How it stores dataeach cue is one line: {startFrame}{endFrame} followed by the text, with | separating multiple display linescues are blocks of an index, a timecode arrow line (HH:MM:SS,mmm --> HH:MM:SS,mmm), one or more text lines, and a blank separator
Strongest atplaying back subtitles that were timed against a specific video ripdelivering captions alongside MP4 or MKV downloads
Weak spotmeaningless without the correct frame rate; the wrong value drifts the whole fileno standard support for advanced styling, voices, or regions
01

Add your SUB file

Drop one or more .sub files onto the converter above, or browse for them. They load into browser memory only — nothing is uploaded, so there is no size-based pricing and no server queue.

02

Pick SRT as the output

Select .srt in the output menu next to each file. The menu only offers targets this engine can genuinely produce, so if SRT is selectable, the route is real and validated.

03

Convert on your device

Press Convert. The package is unzipped in memory and its XML content parsed locally; nothing is uploaded.

04

Verify and download

Each result is signature-checked before the download unlocks, so a failed encode can never masquerade as a valid SRT file. Outputs keep the original filename with the .srt extension.

SUB to SRT questions, answered

Will converting SUB to SRT lose quality?

There is no visual quality to lose — sub is text-oriented and srt is text-oriented, so the question is structural fidelity. Text, ordering, and basic structure are preserved; complex layout, embedded objects, and styling beyond the target's model are simplified.

Is it private to convert SUB files here?

Yes — the .sub file is processed inside your browser tab and never uploaded. The package is unzipped in memory and its XML content parsed locally; nothing is uploaded. Close the tab and the file is gone from memory.

Where will the SRT file work?

VLC, MPC-HC, PotPlayer, Premiere, HandBrake, YouTube, and virtually every desktop player ingest .srt. Browser video elements usually prefer WebVTT, so conversion is common for web delivery.

Will the SRT file be bigger or smaller than my SUB?

It depends on the content: cues are blocks of an index, a timecode arrow line (HH:MM:SS,mmm --> HH:MM:SS,mmm), one or more text lines, and a blank separator. Convert one representative file first and compare before batch-processing a large set.

What happens to the metadata in my SUB file?

In .sub, there is no metadata section; the only header-like content is the frame-rate declaration, which is read on input and written on output. Re-encoding through the browser pipeline does not carry embedded metadata into the output, which doubles as a privacy scrub — check the exported file if you specifically need tags preserved.

Can I convert SRT back to SUB?

Yes — the reverse route exists as a separate tool. Bear in mind that round-tripping .sub → .srt → .sub is not a perfect undo when any lossy step is involved; keep your original if fidelity matters.