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VoiceDeck

Free Subtitle & Caption Tools Tools

Free subtitle and caption tools for editors and producers — convert, validate and retime SRT and VTT files.

Available Tools 12 Always free
FREE

CPL Line-Length Checker

Paste subtitle lines and check each against Netflix, BBC and CJK characters-per-line limits on a visual ruler, with an exact overflow count for every line that's too long.

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FREE

DF/NDF Subtitle Timecode Converter

Convert subtitle timecodes between drop-frame and non-drop at 29.97 or 59.94 fps, with per-line validation and a drift annotation showing how far NDF has slipped from the wall clock — free, instant, in your browser.

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FREE

Netflix CPS Reading-Speed Checker

Check a subtitle event's reading speed (CPS) against Netflix's per-language ceiling — paste the text and timing, see the worked formula and a pass/fail verdict.

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FREE

Premiere Pro Caption Checker

Check captions for Premiere Pro and broadcast specs — characters per line, lines per cue, reading speed (CPS) and cue duration.

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FREE

SRT Validator

Check an SRT file for format errors — numbering, timestamps, overlaps and encoding — and auto-fix them, then download a clean .srt.

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FREE

SRT to TXT Converter

Extract clean plain text from an SRT or VTT subtitle file — strip timestamps and numbers, merge into paragraphs, and download a .txt.

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FREE

SRT to VTT Converter

Convert SRT subtitles to WebVTT (.vtt) in your browser — preview the cues and download a valid .vtt for HTML5 video.

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FREE

Subtitle 2-Frame Gap Calculator

Check the gap between two subtitle events in frames and milliseconds against the 2-frame minimum, with pass/fail verdicts and a mini-timeline — free, instant, runs in your browser.

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FREE

Subtitle Resync Tool

Resync out-of-sync subtitles — shift all cues by an offset or stretch the timing for a new frame rate, for SRT and VTT.

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USES AI

Subtitle Translator

Translate subtitles online — turn an SRT or VTT into another language while keeping every timestamp. Translate captions for any video.

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FREE

TXT to SRT Converter

Convert plain text to a timed SRT subtitle file in your browser. Paste your script, set timing rules, preview the cues and download your .srt — free.

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FREE

VTT to SRT Converter

Convert WebVTT (.vtt) subtitles to a clean, renumbered SRT — strips web styling and cue settings, in your browser.

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