Subtitle Timing Calculator

The Subtitle Timing Calculator helps video editors, translators, and content creators calculate accurate subtitle display times, shift out-of-sync SRT timecodes, and analyze existing subtitle files. It uses industry-standard reading speed guidelines from Netflix, BBC, and the SDI (Subtitling Industry) to ensure viewers have adequate time to read every subtitle.

Subtitle Timing Standards

Reading Speed: The average adult reads subtitles at 250 words per minute (17 characters per second). Children's content uses 160 wpm. Fast readers can manage 300–400 wpm. Netflix standard is 17 cps maximum. Minimum Duration: Subtitles should display for at least 0.8 seconds regardless of word count — this is the minimum time the eye needs to register text. Maximum Duration: No subtitle should stay on screen for more than 7 seconds — it suggests the text is too long and should be broken up. Characters Per Line: Maximum 42 characters per line (Netflix) or 37 cps (BBC) for readability across all screen sizes.

SRT File Format

SRT (SubRip Text) is the most universal subtitle format. Each entry has an index number, a timing line (start --> end in HH:MM:SS,mmm format), the subtitle text, and a blank line separator. Our SRT Parser analyzes any SRT file paste to show word counts, durations, and timing statistics.

Shifting Subtitle Timing

Subtitle sync issues are common when a video is re-encoded, trimmed, or distributed with a different offset from the original. Shifting all timecodes by a fixed offset (positive to delay, negative to advance) corrects the synchronization without re-authoring.