Different Chests contain a different number of different cards. (Values do not include gold card)
Free: 2-4 cards. 3+ Cards usually means Gems, otherwise, Epic or Legendary. 4 cards almost always means Gems and Epic or Legendary cards. 3x chance for Epic or Legendary compared to Silver Chest.
Silver: 2-3 cards. 3 Cards usually means Epic or Legendary cards.
Gold: 4 cards. Usually 1 or 2 of them are Rare cards.
Crown: 5 cards. 1st Card is Gems, 3x chance of Epic or Legendary, and double Card and Gold contents compared to gold.
Giant: 3 cards. At least 1 card is Commons, and at least 1 card is Rares. 3rd card is usually more Rares or Commons, but may be an Epic or Legendary if quotas are already met.
Magical: 7 cards. Quota of Rare and Common cards is usually split between multiple cards. Epics usually in only one card.
Super Magical: 7 cards. Quota of Rare and Common cards may be split between multiple cards. Epics usually come in 1 or 2 cards.
Challenge: 2-9 cards. Same rules apply, scaling is different dependent on progress made in challenge. The exception is the 12 win Electro Wizard Challenge Chest which is like a normal 12 win chest, but the last card is always the Electro Wizard, and the second to last card can be a different Legendary Card.
Clan Crown Chest: 2-9 cards. Same as Challenge Chests
Tournament: 3-9 cards. Same as Challenge Chests
Most of the time, Epics are the last cards revealed in non-Magical/Super Magical Chests. Legendary cards are always the last card revealed in any chest, exept for the largest Tournament chests, if they appear at all. This is because all Cards in a chest will come out in value order, from least valuabe to most valuable.
All chests have the capability of giving up to one above their quota of Rare, Epic, or Legendary cards.
For instance, a quota for an Arena 8 Free Chest is 10 cards, one is garunteed to be a Rare. Their quota for Rares is 1, but it is possible, (though somewhat unlikely) for 2 Rare cards to come out of a Free chest. (This is impossible in Silver Chests below Arena 10 as they never have a rare card quota.
The Chest's quota for Epic and Legendary Cards is 0, but that means that it is possible (Though also EXTREMELY unlikely) for both their to be 6 Commons, 2 Rares, 1 Epic, and 1 Legedary.
If a Chest's Quota is met before the last card, that card is most likely going to be an Epic or Legendary card.
Example: Arena 10 Super Magical Chest Quota: 22 Epics, 136 Rares, 523 Common, 3 Various (Usually more commons, one may be a 23rd Epic, the other might be a Legendary, they may also be a 137th or 138th rare.)
If: Card 1 is 46 Commons, Card 2 is 80 Commons, Card 3 is 144 Commons, Card 4 is 300 Commons, Card 5 is 137 Rares, and Card 6 is 23 Epics, all of the previosly mentioned quotas have been met before the last card comes, Therefore there is an incredibly high chance that Card 7 is a Legendary Card.
If a Chest's Quota is met before the second to last Cards in a chest, there is a high chance of an Epic AND a Legendary to come out of the chest.
Example: Arena 8 Crown Chest Quota: At least 6 Rares
If: Card 1 is 56 Commons, and Card 2 is 6 Rares, both Quotas have already been met with 2 cards left to uncover, because they come out in value order, and because 2 Epics cannot be in one Crown Chest, it can be deduced that Card 3 is 1 Epic, and that Card 4 is a Legendary.