What a tool points at
The longest lines by character count. Useful, and not where this particular problem lives.
Telugu subtitle generator
Telugu captions grow downward too.
Generate an editable Telugu caption track, then check the thing a character count cannot see: Telugu stacks combined consonants below the line, so a caption can pass the width limit and still not fit.
Every line-length rule measures the wrong dimension
Subtitle guidance is written in characters per line. Netflix says 42, broadcasters use less, vertical video less again. All of it is a proxy for one thing: how wide the line is.
Telugu does not only grow wider. When consonants combine, the second is written as a reduced subscript form beneath the first, so a cluster occupies space below the baseline that a single letter would not. A line carrying several of those is physically taller than a line of the same character count without them.
So a Telugu caption can pass every width check you run and still be wrong on screen, usually by having the bottom of a stacked form clipped by the caption box, or by two lines sitting closer together than their content needs. The text is right and the layout is not.
It is worth being direct about the limitation: the subtitle validator and the subtitle line breaker both count characters, like everything else in this category. They will tell you a Telugu line is within the limit, and they cannot tell you it is too tall.
Which lines to check
What to look at
The lines with the most stacked clusters. Often short lines, which is exactly why a character count never surfaces them.
What to do about it
Give yourself vertical headroom by working to a shorter line limit than the character guidance alone suggests, and prefer two lighter lines over one dense one. Neither costs anything, and both make the problem much less likely to appear at all.
When a specific cue is still wrong, rewording it to avoid a heavy cluster is usually faster than fighting the layout. And if the video is going somewhere that accepts a captioned video rather than a subtitle file, exporting it that way settles the layout at export and removes the player font from the equation entirely. The delivery guide covers which destinations take which.
One proofreading note while you are in there. A consonant's subscript form can look quite unlike its full form, so a wrong letter in a stacked position is harder to catch than the same mistake written out. Read those clusters deliberately rather than at speed.
Nearby languages
Kannada shares this stacking behaviour and much of the script's ancestry, so the same vertical check applies there. For the other South Asian languages and the specific fault each one has, see South Asian language subtitles, and for the neighbouring Dravidian languages the Tamil subtitle generator and the Malayalam subtitle generator each cover a different problem again.
Telugu subtitle questions
Why can a Telugu caption fit the line limit and still look wrong?
Because a count says nothing about height. Telugu stacks parts of a syllable vertically, so two cues with the same character count can occupy visibly different amounts of the frame. A limit that works for Latin text is measuring the wrong axis, which is why the check that matters is watching it in the player.
What does that look like in a player?
Usually clipping. The bottom of a stacked conjunct is cut off by the edge of the caption box, or two lines sit closer together than they should and the descenders collide. The text is correct and the layout is not, which is why it survives a check done in a text editor.
How do I catch it?
Preview in the player your audience will use, on a phone if that is where the video is going, and look at the lines with the most conjuncts rather than the longest lines. Those are different lines, and the second is the one a character count will point you at.
What can I do about it?
Set a shorter line limit than the character count alone would suggest, so there is vertical room to spare, and prefer two shorter lines over one dense one. If a specific cue is the problem, rewording it to avoid a heavy cluster is usually quicker than fighting the layout.
Does the subscript form look like the full letter?
Often not. A consonant's subscript form can differ noticeably from its full form, which matters when you are proofreading, because a wrong letter in a stacked position is harder to spot than the same error written out in full.
What can I export?
Reviewed Telugu captions export as SRT or VTT subtitle files, plain text, or a captioned video. A captioned video settles the layout at export, which removes the player font question entirely. Open the caption generator.
Start a Telugu caption track
Transcribe, review the clusters, preview on the device it is going to, then export.