Due to the many questions relating to fasting, merely read the following: Adapted from Taleemul Haqq (basic book for everyday rules) (with minor editions from us) If clarity is lacked in any of the following, do ask! After all, it is your fast!
Things that break one’s fast but make only Qaza wajib*
1. Anything put by force into the mouth of fasting persons.
2. Water goes down the throat whilst gargling, conscious of one’s fasting.
3. To vomit mouthful intentionally or to return vomit down the throat.
4. Swallowing intentionally a pebble, piece of paper or any item that is not used as food or medicine.
5. Swallowing something edible, equal to or bigger than a grain of gram which was stuck between the teeth. However if it is first taken out of the mouth and swallowed, it will break the fast whether it is smaller or bigger than the size of a gram.
6. Inhaling snuff into the nostrils.
7. Swallowing blood (more so if the colour of the blood is more than saliva with which it is mixed.)
8. To eat and drink forgetting that one is fasting and thereafter thinking that the fast is broken, and thus to eat and drink again would constitute a make. (To eat forgetfully in itself does not break the fast)
9. To eat and drink after Subha Sadiq or to break the fast before sunset due to a cloudy sky or a faulty watch etc. and then realizing one’s fault.
*N.B. Any other fast other than a Ramadhaan fast — whether broken intentionally or with a sound valid reason, make ONLY Qaza WAJIB. There is NO Kaffarah for breaking any fast besides that of Ramadhaan.
May Allah (SWT) bless the author(s)
Islam In Action 
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