# Why am I getting less than 5 Ether per block?

Was something changed recently? I've been getting less and less ether per block - is this tied to difficulty level?

I thought difficulty would affect the rate of mining a block, not the number of ether per block. My last block got me 3.75 Ether.

If you got 3.75 ether, this was an uncle mining reward. Kind of the "second place" of mining on Ethereum. You found a solution but someone else found the solution before you. Thankfully for you, it was soon enough from the original block that a reward was paid out.

It's still 5 ether per block for a mining reward.

Update: As of Oct-16-2017 05:22:11 AM +UTC (Block #4370000), it's 3 ether per block

Update: As of Feb-28-2019 07:52:04 PM +UTC (Block #7280000), it's 2 ether per block.

The reduction in ether reward is due to the price increase in Ether. The reductions in block rewards are in an effort to reduce inflation by reducing the newly-available supply of ETH https://media.consensys.net/the-thirdening-what-you-need-to-know-df96599ad857

The mined block is an uncle. The uncle reward formula is (U_n + 8 - B_n) * R / 8 where R is the static reward of 5, U_n is the uncle number and B_n is the block numer, so:

• Uncle 0 : 4.375 ETH
• Uncle 1 : 3.750 ETH

Here's an example:

B_n = 1337, R = 5

U_0 = (1336 + 8 - 1337) * 5 / 8 == 4.375
U_1 = (1335 + 8 - 1337) * 5 / 8 == 3.750
• Thanks. That was really helpful. Two clarifying questions: (1) Is there an official source doc. for this formula? If so, could you add the link? And (2) I was just taking a close look at the Uncles page on etherscan.io and saw that some uncles earned miners 3.125 ETH and 2.5 ETH, so I understand now that these are Uncle 2 and Uncle 3. Can there be Uncle 4 or 5? Is there a limit to how far back from the current block a block can be to qualify as an Uncle? I didn't see anything smaller than 2.5 ETH (but I only scanned a few pages). – Tesa Jul 7 '17 at 20:41
• @Tesa no, the maximum number of uncles, according to specification, is 2 – Nulik Feb 18 '18 at 20:12