Step 1 / source
Add the source media
Source intake
Drop one media file here
Choose an SRT that needs structural cleanup before review or import.
UTF-8 SRT1 SRT / 2 MB
Checking publication status before file selection...
TEMPORARY MEDIA WORKSPACE / SRT FORMATTER
SRT Formatter
Validate and normalize UTF-8 SRT cue numbering, timestamp punctuation, whitespace, and blank-line separation without rewriting caption language.
Request-scoped temporary processingAdd one UTF-8 SRT file up to 2 MB containing no more than 10,000 valid, ordered subtitle cues.No account required
Local API readinessMedia service ready
One bounded job runs per API worker by default.The processor required by this tool is available, and this worker can accept a temporary job.
1 SRT / 2 MB
Temporary server workspace
The selected bytes are sent only to the Nirmion media API for this request. Processing uses a private temporary workspace rather than permanent catalogue storage.
Request-scoped cleanup
Server-side source and result files are removed when the response stream closes. Re-downloads use the result Blob retained only in this browser tab.
Original stays unchanged
Nirmion writes a separately named result containing nirmion_tools and never overwrites the selected source file.
Know the product contract
What goes in, what changes, what comes back
Every media page documents the accepted source, the selected FFmpeg transformation, the output container, and the limits that can affect the job.
Prepare the source
Keep a source copy and confirm that every intended caption has a timing line and at least one text line.
Apply one operation
The parser validates ordered cue blocks, rewrites sequential numbering, standardizes comma timestamps, collapses horizontal whitespace, and restores blank separators.
Receive a separate file
Import the result into the destination editor and review line breaks, timing, tags, and language.
Plain-language method
What SRT formatting changes
Formatting improves structure but does not spell-check, translate, reflow long captions, or verify synchronization against media.
- 01Choose valid source media
Keep a source copy and confirm that every intended caption has a timing line and at least one text line.
- 02Review the operation settings
No settings are needed; malformed or reversed cue times are rejected instead of guessed.
- 03Inspect and download the result
Import the result into the destination editor and review line breaks, timing, tags, and language.
Useful when
Practical jobs this tool handles
- Normalize subtitle exports from mixed editors.
- Repair inconsistent cue numbering.
- Prepare an SRT for deterministic version review.
Before processing
Check the source and output choices first
- Retain the source copy.
- Confirm cue text is complete.
- Review tags in the destination player.
- Test synchronization separately.
Container and codec
Understand the output format
The output uses UTF-8, sequential cue numbers, HH:MM:SS,mmm timing, and one blank line between cues.
Know the boundary
Structure validation is not caption quality review
The tool cannot judge reading speed, accessibility, speaker identification, spelling, or timing against audio.
Quick answers
Questions before you process media
These answers describe the actual upload, FFmpeg processing, download, and temporary-retention contract.
Will it change caption wording?
No. It only trims horizontal whitespace around retained lines.
Will it fix invalid timing?
No. Invalid or reversed times are rejected.
Does it translate captions?
No.