"Double Pinyin" is a pinyin-based input method. Compared to full pinyin, it has the characteristics of fewer keystrokes and a stronger typing rhythm. It is also simple and easy to learn. According to personal experience, proficiency can be achieved in about a month of practice, and it can exceed 20% of the input speed of full pinyin in three months (calculated at 60 characters per minute for full pinyin).
Like the commonly used full pinyin and the legendary Wubi, double pinyin is also an input method, not a specific input method software. Like full pinyin, the input methods built into mainstream operating systems support double pinyin.
Let's review pinyin first. Most pinyin consists of an initial consonant followed by a final vowel (a few have no initial consonant and are composed only of a final vowel).
Initial consonants:
b p m f d t n l
g k h j q x
zh ch sh r z c s
w y
Final vowels:
a o e ai ei ao ou an en ang eng ong
i ia ie iao iou(iu) ian in iang ing iong
u ua uo uai uei(ui) uan uen(un) uang ueng(eng)
ü üe(ue) üan(uan) ün(un)
Double pinyin maps both the initial consonants and final vowels to specific keys on the keyboard. Each character only requires two keystrokes, one for the initial consonant and one for the final vowel. For example, for the character "双" (shuāng), you only need to press the key corresponding to "sh" and the key corresponding to "uang".
To conform to habits, single-letter initial consonants and final vowels in double pinyin are directly mapped to the keys corresponding to the letters. For example, "哈" (hā) is input the same way as full pinyin. For initial consonants composed of multiple letters such as zh, ch, and sh, they are mapped to non-initial consonant keys such as v, i, and u.
Someone has conducted a test (https://zhuanlan.zhihu.com/p/34438126), using full pinyin, an average of 2.9 keystrokes are required for each character. In double pinyin, each character requires a fixed 2 keystrokes, compared to full pinyin, double pinyin can reduce keystrokes by 31% ((2.9-2)/2.9=0.31), and improve input efficiency by 45% ((2.9/2-1)/1=0.45), which can be said to be a significant improvement.
Using double pinyin can not only reduce keystrokes and improve input efficiency, but also better conform to the design of pinyin with initial consonants and final vowels.
Compared to the widely used full pinyin input method, the advantage of the double pinyin input method lies in the number of keystrokes.
As a modified pinyin input method, double pinyin has a long history and can be directly used in input methods on major platforms, and there are many syntax options.
Among all the mainstream options, the ones I personally recommend the most are Xiaohe Double Pinyin and Natural Code Double Pinyin. If you are an iOS/macOS user, the recommended range narrows down to Xiaohe Double Pinyin. In addition to the native support of the system input method, there are mainly two reasons.
First, these two options avoid using the ";" key for the final vowels (such as Microsoft/Sogou Pinyin and Ziguang Pinyin, ; - ing), so they do not change the keyboard layout on mobile platforms. Because when some Android input methods encounter double pinyin schemes that use the semicolon key, they will not change the keyboard layout to accommodate an additional button, but will move the final vowel to another existing button, such as the lower left corner to avoid ambiguity. Although the semicolon is not so important in double pinyin schemes, such changes would disrupt muscle memory.
Second, these two options do not use a fixed zero-initial consonant scheme. The so-called "zero-initial consonant" refers to designating a specific key on the keyboard as a zero-initial consonant, which, when combined with a final vowel key, is used to input characters composed solely of final vowels. For example, in the Microsoft double pinyin scheme, "按" (àn) is input as "oj". Xiaohe and Natural Code set the zero-initial consonant as the first letter of the final vowel. As a result, two-letter characters composed of pure final vowels can be identical to full pinyin, and single-letter characters of pure final vowels can be input by double-clicking the key, reducing the difficulty of adaptation.
Practice of Double Pinyin Schemes#
The author of the article "Making Double Pinyin No Longer an Input Method Only for a Few People" has developed a very suitable practice website, Double Pinyin Practice @ BlueSky (https://api.ihint.me/shuang/). The website provides both a web version and a WeChat mini program, supporting 17 double pinyin schemes, and the website is also perfectly compatible with mobile viewing.