Check subtitle reading speed (CPS & WPM), character count, and platform compliance for Netflix, BBC, Amazon, Disney+ & more — instantly.
0 characters · 0 words · 0 lines
Or enter hours/minutes/seconds (HH:MM:SS.mmm) for SRT-style timecodes:
Leave timecode blank to use seconds directly.
Shows compliance for the selected platform, plus a full platform comparison table.
Standard: 42 for most platforms; 37 for BBC; 32 for US broadcast (FCC/CEA-608).
Enter your subtitle text in the text area — the tool counts characters, words, and lines instantly. Set the display duration in seconds, or paste an SRT-style timecode difference (e.g. 00:00:03,250). The calculator computes CPS, WPM, checks your lines against the CPL limit, and rates compliance across six major platforms simultaneously.
| Platform | Max CPS (Adult) | Max CPS (Kids/SDH) | Max CPL | Min Duration |
|---|---|---|---|---|
| Netflix | 20 | 17 | 42 | 0.833 s (⅚ s) |
| Amazon Prime | 20 | 17 | 42 | ~1 s |
| Disney+ | 17 | 17 | 42 | ~1 s |
| BBC | 15 | 12 | 37 | 1 s |
| YouTube / General | 25 | 17 | 42 | 1 s |
| US Broadcast (FCC) | 17 | 17 | 32 | 1 s |
| Recommended (general) | 17 | 12 | 42 | 1 s |
Sources: Netflix Partner Help Center Timed Text Style Guide; BBC Subtitle Guidelines; Amazon Prime Direct Publishing requirements. Platform guidelines are updated periodically — always verify against the current official style guide for your specific delivery.
CPS (Characters Per Second) is the primary reading-speed metric in professional subtitling. It is calculated as: CPS = total characters ÷ display duration (seconds). Unlike words per minute (WPM), CPS is language-independent — a 17 CPS cap applies equally to English, Spanish, and French text, whereas WPM comparisons break down across languages because average word lengths differ significantly.
This calculator counts every visible character including letters, punctuation, spaces, and hyphens. Line break characters are not counted. Some platforms and tools differ slightly (e.g. Japanese-specific half-width character rules), but the standard approach counts all characters including spaces. Spaces-excluded counting is used by some broadcasters — the tool shows both on request via the character bar detail.
What is CPS in subtitling?
CPS stands for Characters Per Second — the number of characters a viewer must read each second to follow a subtitle. It is calculated by dividing the subtitle's total character count by its display duration in seconds. CPS is the primary reading-speed metric used by Netflix, Amazon, Disney+, and professional subtitlers worldwide because it works consistently across all languages, unlike WPM.
What CPS does Netflix allow?
Netflix allows a maximum of 20 CPS for adult English content and 17 CPS for children's content. Reading speed violations are among the most common causes of Netflix subtitle file rejections. Professional subtitlers often target 15–17 CPS voluntarily, as this gives a broader audience — including older viewers and those with reading difficulties — enough time to read each cue comfortably.
How many characters per line does Netflix allow?
Netflix specifies a maximum of 42 characters per line (CPL) for most Latin-alphabet languages. Text should stay on one line unless it exceeds 42 characters, in which case it can extend to two lines. Line breaks must follow natural syntactic boundaries — after punctuation or before conjunctions — and must never split a noun from its article or a first name from a last name.
What is the difference between CPS and WPM for subtitles?
CPS (characters per second) is language-independent; WPM (words per minute) is not. A word in German averages more characters than a word in Chinese or English, so WPM comparisons are misleading across languages. Netflix and most streaming platforms use CPS. WPM remains common in UK broadcast contexts (the BBC targets 160–180 WPM, approximately 15 CPS). This calculator reports both.
What is the minimum subtitle display duration?
Netflix sets its minimum at ⅚ of a second (approximately 0.833 s). Most other platforms and broadcast standards — BBC, Amazon, Disney+, and general SDH guidelines — require at least 1 second. Very short single-word subtitles may technically pass CPS but still feel like a flash to viewers, so 1 second is the widely recommended floor in practice.
How do I fix a subtitle that is over the CPS limit?
Two approaches: (1) Condense the text — shorten or paraphrase the subtitle to reduce character count while preserving meaning. This is the standard professional approach. (2) Extend the display duration — stretch the in/out timing if dialogue pacing allows. The Recommendation panel in this calculator tells you the maximum characters allowed for your current duration and the minimum duration for your current text at your chosen CPS limit.
Do spaces count in CPS?
Yes, for most platform standards, all visible characters — including letters, punctuation, and spaces — are counted. This calculator counts spaces by default, matching the Netflix and industry standard. Some older broadcast tools exclude spaces; if you need a spaces-excluded count, check the character detail bar in the results panel which shows both counts.
Estimates & guidance only. Platform guidelines are updated periodically. Always verify against the current official style guide for your specific delivery platform and language pair before submission. This tool does not replace a professional subtitle QC review.