Rules for romaji in Tatoeba

The rules in general

In general, you would follow this chart.
Exceptions : 

• ふ => fu (and not hu)
• づ => dzu (and not zu) to differentiate it from ず which is already converted as 'zu'

About particles

• は => wa (and not ha)
  
• を => o (and not wo)
  
• へ => e (and not he)

About the ん

• ん(n') when followed by a vowel. けんい(ken'i).
  
• ん(n) if else. こんにちは(konnichiwa).
  

About the ~おう

• No matter the situation, ~おう is converted as ~ou. 東京(toukyou), だろう(darou). Not Tôkyô or darô.
  
• I would like to avoid accents because it's really not practical for those who don't have this accent on their keyboard.

About katakana and capital letters

• Katakana always in capital letters. パソコン(PASOKON).
  
• And capital letters ONLY for katakana! Which means you won't use a capital letter at the beginning of a sentence.
  

About the ー in katakana

• Don't double the vowel, use -. ゲーム(GE-MU).
  

About ティ, ディ

• ティ(TI). パーティ(PA-TI).
  
• Same thing with DI. ヂ(JI),　ディ(DI).
  

About spacing

• Spacing is very annoying, and so far we don't have rules for everything. In case we didn't indicate what to do, just do whatever you feel is right.
  
• Always put a space after a -te verb. 食べています(tabete imasu), やってみて(yatte mite), 愛してる(aishite ru).
  
• Na adjectives : no space. 上手な(jouzuna), ばかな(bakana), 本当な(hontouna)
  
• Space before に if it's after an adjective : 上手に(jouzu ni), 本当に(hontou ni)
  
• No space between masu and radical : "wakarimasu", and not "wakari masu"
  
• In case two particles are following each other, we do not have rules yet. I usually don't put spaces for "noni", "node", "demo". But I usually put a space for "ni wa", "de wa" (except dewa nai), "ni mo"...
  
• Space before -にくい, -やすい, -ながら, -つづける, etc.

About the quotes

• Don't use 「」in the romaji. Use the double quotes.
  
• For instance : 「何時ですか」「１０時半です」 = "nanji desu ka" "juuji han desu"

Honorific prefixes お and ご

You'd have to add a hyphen after "o" or "go".

• お誕生日 : o-tanjoubi
  
• ご紹介 : go-shokai