Why this tool is useful
Use Split Subtitles at an Exact Timestamp when you need to divide one SRT or WebVTT timeline into two normalized SRT files inside a ZIP archive while keeping the source file on your device.

divide one SRT or WebVTT timeline into two normalized SRT files inside a ZIP archive entirely in your browser without uploading the selected file.
Ready. Your working data stays in this browser.
Files stay on this device. Processing uses browser APIs only; nothing is uploaded to YTSave, the media API or a proxy.
Use Split Subtitles at an Exact Timestamp when you need to divide one SRT or WebVTT timeline into two normalized SRT files inside a ZIP archive while keeping the source file on your device.
The browser validates the declared file type and 10 MiB limit, then runs the subtitle split operation locally. No downloader job or proxy is involved.
Choose a supported file, review the locally produced subtitle parts, and download a result only when this operation creates one.
The calculation is deterministic and explains validation errors instead of silently changing invalid input.
Input and output remain in this tab. Copy and download happen through browser APIs without a server upload.
Every run reports its tool mode, timestamp and input/output size so transformed data can be audited.