Frequently Asked Questions

Yes, it's completely free! No registration required, and there are no conversion limits. The service is supported by ads, and all features are available at no cost.

No, not at all! All conversion is processed 100% in your browser. Files are never sent to our server, so there are no privacy concerns.

Yes, it works perfectly on smartphones and tablets. Our responsive design ensures a great experience on any screen size.

We support all modern browsers including Chrome, Firefox, Safari, and Edge. Internet Explorer is not supported.

It depends on your needs.

• SRT: Excellent compatibility, worldwide use, easy to edit
• SMI: Popular in Korea, supports styling

View detailed comparison →

When converting SMI to SRT, some styles may be lost. This is because SRT only supports limited styling by default. Text content and timing are perfectly preserved.

Currently, only one file can be converted at a time. Batch conversion is planned for a future update.

Please check your browser's popup blocker. Allow popups for smisrt.com and the download should work normally. Also check your browser's download folder.

If subtitles appear before the dialogue, enter a positive number. For example, if subtitles are 2 seconds early, enter +2 in the sync adjustment.

If subtitles appear after the dialogue, enter a negative number. For example, if subtitles are 3 seconds late, enter -3 in the sync adjustment.

Yes! You can make precise adjustments using decimals like 0.5, 1.25, -2.5, etc.

This is caused by frame rate differences. Simple sync adjustment won't fix it - you need frame rate conversion. View sync guide →

This is an encoding issue. Our tool automatically detects encoding, but some files may need manual verification. View encoding guide →

Both are character encoding methods.

• UTF-8: Supports all world languages, current standard
• EUC-KR: Korean only, older standard

UTF-8 is recommended for modern subtitles.

Yes, we support all languages if the subtitles are UTF-8 encoded. Other encodings like Shift_JIS (Japanese) and GB2312 (Simplified Chinese) are also auto-detected.

Since processing is done in the browser, there's theoretically no limit. However, very large files (tens of MB) may take longer to process. Typical subtitle files (a few hundred KB) are processed instantly.

Currently, we don't provide a public API. If you need bulk conversion, please contact us via email.

Once you load the page, conversion works offline too. This is because all processing is done in the browser.

Please send bug reports or feature suggestions via email. We'll fix issues as quickly as possible.