What many viewers don’t realise is that there are strict guidelines in place when it comes to subtitling. First and possibly most importantly, subtitles cannot exceed a certain reading speed. A reading speed is a sophisticated calculation of how many words per minute or characters per second a person can comfortably read, which takes into account the number of lines, characters per line and how long the subtitle is cued to stay on-screen.
If a subtitle’s reading speed is too high, the viewer will spend all of his or her time reading but if the reading speed is too low, the viewer may re-read the subtitle. There’s definitely a balance that must be achieved! We at GoLocalise aim to never exceed a reading speed of 20 characters per second as this ensures that the reader will have enough time to read and enjoy what’s on screen. One of the most helpful ways to reduce the reading speed is to reduce the text within the subtitle, even if it means replacing the original spoken word with an alternative which means the same thing.
In the images below, the numbers ‘34’ and ‘16’ in green represent the number of characters per line. The numbers in red and yellow represent the reading speed. Since the top subtitle exceeds the maximum reading speed, the text has been reduced in order to achieve an acceptable speed.
Some other limitations inflicted upon the art of subtitling are, as mentioned before, the maximum number of characters per line and maximum number of lines per subtitle. These maximums vary by country and company, but GoLocalise’s subtitling guidelines require a maximum of 39 characters per line and 2 lines per subtitle. Since people tend to speak quickly (and almost always without taking into account that their speech is going to be subtitled) converting spoken word to written word can often be a challenging task. It takes practice and some discretion when it comes to reducing text to create the perfect cookie-cutter subtitle that abides by all of the above subtitling rules.