Donation Machine

The Donation Machine is a type of machine that appears in almost every Shop as well as rarely spawning through Black Markets, Reward Plates, Arcades, and Vaults.

Touching the Donation Machine donates a coin from Isaac's inventory, increasing the displayed coin total by one. Similar to the Greed Donation Machine, the number of coins donated persists between runs. Donating enough money upgrades the Shop, the Library, and unlocks new items.

It takes many runs of continuous donations to unlock everything, as the player will have to donate a total of 999 coins to max the machine out.

Mechanics[ | ]

A total of 999 coins can be donated. Attempting to donate a 1000th coin explodes the Donation Machine, resetting its total back to 0 and dropping roughly 12 dimes.

Donating money has a chance to jam the machine, preventing further donations. If a machine jams, ALL future Donation Machines will be jammed as well for the remainder of the run.

On average, a Donation Machine accepts 30 coins before jamming each run. Each coin has a 5% chance to jam the machine.
A Donation Machine now accepts 30 coins on average before jamming. The first coin has a 0.15% chance to jam the machine, increasing by 0.15% with each coin donated on the current floor. Restarting a run with R Key un-jams all Donation Machines.

Exploding the Donation Machine, such as with a Bomb, causes it to drop 1-5 pennies / 6-14 pennies. This decreases the donation total by (number of dropped pennies + 1), resulting in a net loss.

The Donation Machine can be exploded for as long as there are still coins inside. It drops coins even when jammed.
- Humbleing Bundle turns the dropped pennies into double pennies, which makes a profit.
Bombing a Donation Machine destroys it, and future Donation Machines will not appear for the rest of the run. The coins it drops is deducted from the donation total at the start of the next run.
- Jammed donation machines cannot be blown up and will not drop any coins.
- Using R Key un-explodes the Donation Machine, allowing it to spawn again.

Under rare conditions, it's possible to spawn multiple donation machines in the same room, via Reward Plates or TMTRAINER. Adding coins to one does not update the coin counter on the others, until the current room is left and re-entered. They can be individually jammed/exploded without affecting the other.

Other Effects[ | ]

Donations have a 2% chance to increase Isaac's luck by 1.
- Donating ten coins to a Donation Machine increases the odds of an Angel Room appearing instead of a Devil Room, if a devil deal was not previously taken. This does not increase the chance overall, instead simply swaying the odds in favor of an Angel Room.
Donation Machines cannot appear while achievements are disabled.

Donation chances[ | ]

Below is a table of the expected probabilities that donating any amount of coins jams the Donation Machine, assuming every donation has an independent 5% chance to cause a jam.

Pre-Repentance Jam Odds
Coins donated	Total jam chance	Notes
0	0%	The total jam chance is considered the probability of a jam at donating $n$ amount of coins.
1	5%	It is possible for the machine to jam after donating a single coin.
2	9.75%
3	14.26%
4	18.55%
5	22.62%	The amount of coins a Nickel gives you
10	40.12%	The amount of coins a Dime gives you
13	48.67%	Average low
14	51.23%	Average high
25	72.26%	The amount of coins A Quarter gives you
50	92.31%
99	99.38%	The maximum amount of coins Isaac can normally carry.
148	99.95%	The amount of coins that can be donated at once with 99 coins and proper usage of a 2 of Diamonds card
$n$	$1 - 0.95^n$	To calculate the odds of the machine not jamming after $n$ donations, use the formula $0.95^n$ . This graph can also be used to calculate any probabilities.

Below is a table of the expected probabilities that donating any amount of coins will jam the Donation Machine. The jam chance resets upon entering a new floor.

Repentance Jam Odds
Coins donated	Total chance	Jam chance on donation	Notes
0	0%	0%	The total jam chance is considered the probability of a jam at donating $n$ amount of coins.
1	0.15%	0.15%	It is possible for the machine to jam after donating a single coin.
2	0.6%	0.3%
3	1.34%	0.45%
4	2.38%	0.6%
5	3.69%	0.75%	The amount of coins a Nickel gives you
10	14.02%	1.5%	The amount of coins a Dime gives you
20	45.62%	3%
21	48.93%	3.15%	Average low
22	52.2%	3.3%	Average high
25	61.53%	3.75%	The amount of coins A Quarter gives you
50	97.97%	7.5%
99	~99.99%	14.85%	The maximum amount of coins Isaac can carry without Deep Pockets
148	~100%	22.2%	The amount of coins that can be donated at once with 99 coins and proper usage of a 2 of Diamonds card
667	~100%	100.1%	The Maximum amount of coins possible to donate on a single floor.

Donation Rewards[ | ]

Blue Map - Donate 10 Coins to the Donation Machine.

Store Upgrade lv.1 - Donate 20 Coins to the Donation Machine.

There's Options - Donate 50 Coins to the Donation Machine.

Store Upgrade lv.2 - Donate 100 Coins to the Donation Machine.

Black Candle - Donate 150 Coins to the Donation Machine.

Store Upgrade lv.3 - Donate 200 Coins to the Donation Machine.

Red Candle - Donate 400 Coins to the Donation Machine.

Store Upgrade lv.4 - Donate 600 Coins to the Donation Machine.

Blue Candle - Donate 900 coins to the Donation Machine.

Stop Watch - Donate 999 Coins to the Donation Machine.

Strategy[ | ]

After reaching 999 coins and unlocking everything, the Donation Machine can be exploded freely, essentially letting Isaac trade bombs for the stowed away coins.

Causing the Donation Machine to explode by reaching 1000 cents is not recommended, as it does not unlock anything and limits the ability to trade bombs for coins in future runs until the coin total has been built back up again.
It is recommended to deliberately bomb the Donation Machine such that the banked total is less than 999 cents. This effectively prevents accidental 1000th cent donations.

With items that let Isaac reliably create explosions, such as Ipecac, and Dr. Fetus, the donation machine can be endlessly bombed for as long as there are still coins inside of it, as it doesn't get destroyed after a single explosion like it does in Repentance runs. This can have game-breaking potential, especially if combined with items like Humbleing Bundle, D20, Rune of Jera, and Restock.

Making Money[ | ]

Though it is generally best to donate coins in addition to playing the game normally (to obtain other unlocks/completion marks in addition to filling it up), if the player wishes to deliberately farm coins to fill the Donation Machine sooner, there are multiple ways to do so.

Blood Donation Machines/IV Bag can generate a lot of money, at the cost of health.
- If there's an abundance of Red Hearts on the floor (or Placenta and a lot of patience), enough money can be generated with blood donations to jam the machine.
Azazel's powerful attack and innate flight makes it easy for him to clear rooms and fly to otherwise hard to reach coins, making him a good choice for farming coins early on.
- Keeper and Tainted Keeper can get a lot of money incredibly fast with their unique starting items and abilities, though by the time they (and Keeper's starting items) are unlocked, it is likely that a high donation total would already be achieved. Regardless, they're still great at refilling the machine for the benefit of future runs.
In versions of the game prior to Booster Pack #5, Glowing Hourglass un-jams the machine and returns the donated coins, but the donation total still goes up as if they were donated. There are multiple ways to donate indefinitely with this, usually by charging it up before leaving the room:
- Purchasing (or otherwise acquiring) a Lil' Battery to recharge Glowing Hourglass in the shop will rewind to back before the battery was purchased.
- Using Sharp Plug (or Habit and two bombs) with more than two hearts provides a full charge.
- If Glowing Hourglass is for sale in the Shop, it can be bought before donating, then used to go back before it was purchased.
- Using a ? Card, which takes Isaac back to before it was used, allowing infinite uses of Glowing Hourglass.

Force Quit Method (cheating). This is an easy way to fill up the machine potentially in one run. This method also has no item prerequisite. The game saves the normal and Greed Donation Machine data separately from your main save file; the machine data is only changed and saved AFTER you leave the room.
- Enter a room with the Donation Machine. Then exit to the start menu normally to save your game.
- Continue the game.
- Donate money until machine jams or you run out of coins.
- Walk out to a different room. Now the game will save the change in coins only.
  - On computer, you will not need to leave the room but will need to suspend the game using an application such as Process Explorer (for Windows)
- Force quit the game
  - Windows: Alt+F4
  - OS X: Force Quit
  - Linux: Ctrl+Alt+Esc (may depend on desktop environment)
  - Consoles: home button and then quit app
  - Nintendo Switch: eject and reinsert the cartridge
- Restart and continue the game. Your save game from the 1st step will be restored. It should look the same as before: the Donation Machine is unjammed, but the starting coin count on the Donation Machine is now higher.
- Donate money. Walk to different room. Force Quit. Repeat.
- Notes: If you accidentally walk by the machine at 999 coins and blow it up by accident, do not leave the room and just Force Quit. The machine will be back at 999.
  - Despite the 5% jam chance noted above, in actuality, the number of coins it takes to jam a machine is set per floor. Let's say it takes 10 coins to jam the machine. If you Force Quit and try again, it will still take 10 coins to jam the machine even with the higher coin count. When you go to the next floor, let's say it now takes 20 coins to jam the machine. Force quitting on the next floor will still take 20 coins to jam the machine next time. The method works best on a Donation Machine that accepts a large number of coins before jamming.

Bugs[ | ]

Bug!	Vita If Isaac donates to the machine, leaves the room, and the game is then restarted using the PS button, the machine will retain its donation and Isaac will have the same amount of coins as he started the current floor with.