The math of video, done for you
Timecode, bitrates, read times, subtitle sync — the small calculations that eat up an editor's day, turned into instant tools. Built by people who work in post-production.
Video & post-production
Timecode Calculator
Add, subtract and convert SMPTE timecode at any frame rate — with proper 29.97/59.94 drop frame handling.
Bitrate & File Size Calculator
Estimate export sizes, or find the bitrate that hits a target file size. YouTube, Twitch and 4K presets included.
SD Card Recording Time
How much video fits on your card? Recording time for any capacity and bitrate, with camera presets.
Subtitle Sync & Converter
Fix out-of-sync SRT/VTT subtitles: shift by milliseconds, retime between frame rates, convert formats.
Subtitle Translator & Bilingual SRT Maker
Match TXT/DOCX translations to SRT/VTT timecodes, create bilingual subtitles, edit cues, and run local delivery checks.
SRT to Text
Turn subtitles into a clean transcript — strip timestamps, merge paragraphs, download as .txt.
Subtitle Format Converter
SBV, ASS/SSA, LRC, SRT, VTT — auto-detected and converted, right in your browser.
Extract Audio from Video
Pull the audio track out as M4A (lossless), MP3 or WAV — no upload, no watermark. Practical size depends on device memory.
MKV to MP4
Lossless container swap in your browser — zero quality loss and no upload. Practical size depends on device memory.
Video to Text (AI)
Free Whisper transcription on your device — export transcripts or SRT/VTT subtitles. ~100 languages.
Screenwriting & AI creation
Beat Sheet Calculator
Save the Cat's 15 beats mapped to your exact page count or novel word count.
Screenplay Length Calculator
Pages to screen time and back — with standard lengths for features, TV episodes, shorts and mini-dramas.
Logline Generator
Your story in one sentence, built from three proven pitch-room formulas. No AI — ideas stay on your device.
Script Timer
Paste a script, get its spoken duration at voice-over pace — with 15s / 30s / 60s commercial benchmarks.
AI Video Prompt Generator
Build cinematic prompts for Veo 3, Sora, Kling, Runway and Seedance — shot type, camera moves and lighting like a real DP.
Prompt Template Library
Copy-paste templates for AI video and image generation — commercials, UGC ads, portraits, storyboards.
Why FrameMath?
Every editor knows the moment: you're mid-session and need to add two timecodes, check whether a 4K export fits the delivery limit, or figure out why the subtitles drift. The answers are simple math — but doing that math by hand at 2 a.m. is how mistakes get into masters.
FrameMath is a growing set of single-purpose tools that answer those questions instantly. No accounts and no watermarks. Local Tools run entirely in your browser. Online translation is clearly labeled and sends subtitle text only to Google Cloud — never video or audio files.
Want the theory behind the tools? Read our guides on drop frame timecode, bitrate selection, subtitle formats and more.