Hanyu Pinyin is the romanization system used in the People's Republic of China for Standard Mandarin. It is also the system most learners meet first. Each Chinese syllable is written with Latin letters. Tones are written with marks over vowels or, in some tools, with numbers.
Pinyin is for pronunciation and input. It is not a replacement for characters in formal writing, and it is not English.
Initials, finals, tones
A syllable such as zhong has an initial (zh) and a final (ong). The first tone is written zhōng. The same letters with another tone are a different syllable to a Mandarin speaker.
What this site can do
The Pinyin converter reads Chinese characters and writes Pinyin. The Pinyin Writer is for people who already type letters and tone numbers.
Continue with the four tones or tone marks vs tone numbers.