Mining and Token Rewards
While there's no exact formula for calculating how much
HNT you'll earn
over a given period, there are some higher level concepts, design elements, and
rules to keep in mind that will help better explain what you might earn and why.
This section covers these, as well as some mining and token reward basics.
How Do Hotspots Earn Helium Tokens?
The Helium blockchain rewards Hotspots for providing wireless coverage and verifying the Helium Network. Hotspots are rewarded in Helium Token, $HNT.
Every epoch, the current consensus group mines approximately 30 blocks on the blockchain. In each block, Hotspots perform various types of work and are awarded according to the following distribution:
|PoC Challenger||Rewarded to any Hotspot that creates a valid PoC challenge and submits the corresponding receipt to the blockchain.|
|PoC Challengees||Awarded to any Hotspot that transmits a POC packet after being targeted by the challenger.|
|Witnesses||Distributed to all Hotspots that witness a beacon packet as part of a PoC Challenge.|
|Consensus Group||Divided equally among the 16 Hotspots that are part of outgoing Consensus Group, responsible for mining blocks.|
|Security||Awarded to Helium, Inc and other Network investors who hold Security Tokens.|
|Network Data Transfer||Distributed each epoch to Hotspots that route LongFi sensor data for sensors on the Network during that epoch.|
Do I Have To Actively Participate to Earn Rewards Once My Hotspot is Deployed?
No. Once your Hotspot is completely deployed and fully synced with the Helium blockchain, you as the owner are not required to do anything else in order to earn $HNT. Your Hotspot will perform all of the above activities on its own while it runs.
Target $HNT Production Per Epoch
The target production rate for new $HNT minted per month is
means that, if the blockchain performs as designed, it will produce
HNT per month. This target rate is based on the following two parameters, as
defined in their specific chain variables:
- Target block time is
- Target epoch size is
Recall that, in the Helium blockchain, blocks contain some number of individual transactions, and epochs are comprised of all the blocks mined by the current Consensus Group since the last epoch.
So, if the Network achieves its target block time of
60 seconds, and target
30 blocks, the blockchain will produce 5,000,000 HNT per month. Per
epoch, this equals roughly
3424.66 HNT. The math for this is as follows:
(43800 minutes per month / 30 minutes per epoch) = 1460 epochs per month
(5000000 tokens minted per month / 1460 epochs per month) = 3424.65753424658 HNT per epoch
What Are The Current Block and Epoch Times?
At any point you can go to the Helium blockchain Explorer to view recent block and epoch statistics, past $HNT production numbers, and much more. Your Helium Mobile Wallet will also give you the average block and epoch times for the trailing 24 hour period.
HNT Distributions Per Epoch
As calculated above, the target
HNT per epoch is approximately
next logical question is, "Where does all this HNT go?" Let's take a look.
Below are the mining rewards per epoch. For every complete epoch, marked by the
election of a new Consensus Group, all the
HNT produced get distributed over
the following reward types:
|Reward Type||Percentage||HNT Earned by Reward Type|
|Network Data Transfer||Up to 32.5%||Up to 1113.0145|
Rewards Change Over Time
In the above table you can see the maximum allotted rewards per reward type in accordance with HIP 10 (described below). If you want to see the current reward type percentage, you can always query the Chain Variables API. The next maximum allotted rewards change is currently scheduled for August 1, 2021.
HIP10 and Variable HNT Rewards for Network Data Transfer
As noted above,
HIP10 was activated on August 24th, 2020.
HIP10 was introduced by Helium Community Member
hashc0de and was adopted by
the Helium Community. It ensures that $HNT is rewarded at a rate of 1:1 to the
amount of Data Credits (DCs) routed by any given Hotspot per epoch. In doing so,
the Network Data Transfer reward is proportional to the DC spent that epoch.
This proportional relationship between Network Data Transfer reward type and DC
is capped at 32.5% (1113.0145 HNT). Therefore, if the DC burned doesn't equal
the value of
1113.0145 HNT, the remaining HNT is redistributed to the Proof of
Coverage (PoC) rewards groups pro-rata.
Here are a few examples to illustrate how this works in practice:
Example 1: DC Burn does not exceed 32.5% HNT
- In a given epoch,
2,000,000DCs are transferred across the network
- The HNT Oracle Price is
- In this scenario, total HNT value of DC transferred in this epoch is
10HNT. This calculation is:
(2,000,000 DC * $0.00001 / $2 HNT Oracle Price)
10 HNTwould be split proportionally to the Hotspots who did the work routing packets at the 1:1 rate.
- The remaining
1103.0145 HNTfrom the Network Data Transfer reward would be distributed ratably among the Challengers, Witnesses and Challengees.
38.10413727to the Challenger group
851.9282902to the Witness group
212.9820725to the Challengee group
Example 2: DC Burn exceeds 32.5% HNT
- In a given epoch,
500,000,000DCs are spent on data transfer across the network
- The HNT Oracle Price is
In this scenario, total HNT value of DC transferred in this epoch is
This calculation is:
(500,000,000 DC * $0.00001 / $2 HNT Oracle Price)
- Because the Network DC burn exceeded the
1113.0145HNTavailable to the Network Data Transfer reward, all Hotspots who did the work over this epoch with split the full
Additional Notes on Reward Types and Payouts
- All Hotspots in the
Consensusgroup will earn an equal reward.
- All Hotspots participating in PoC, including
Witnesseswill earn rewards proportional to how many events they participated in out of the total number of events per epoch.
- All Hotspots participating in
Network Data Transferwill earn rewards proportional to their share of the total data transfer in that epoch, as shown above.
- Hotspots can earn one or more reward types during any given epoch.
- Hotspots are only eligible to submit one Proof of Coverage Challenge - which
results in them earning the
PoC Challengerreward - once per 120 blocks.
PoC Challengee, and
Witnessreward types get distributed in the epoch that includes the corresponding PoC receipt.
- A Hotspots can earn more than one
Witnessrewards per epoch.
HNT Proration and Slow Block Times
The Helium blockchain is still new and growing quickly, so there are bugs to be
squashed and optimizations to be made. Target block and epoch times can be
difficult to attain consistently. To account for this, the Helium blockchain
uses something called
proration to ensure that the target of
achieved even if block and epoch times aren't on target.
Target HNT Depends on Blocks, Not Clocks
It's easiest to think of target HNT production over the span of one month. If
the blockchain performs on target, resulting in roughly 1460 epochs per month,
5,000,000 new HNT will be produced. "One month" is a period of time
measured by a clock. However, under the hood, we use block time, and the
resulting epochs, to mark HNT production against our target. So when blocks are
slow, HNT production is reduced proportionally.
What Happens to HNT When Block Times are Slow?
Occasionally, due to the rapid growth of the network, there can be
less-than-optimal block times. This results in slower epochs. When this happens
the blockchain will produce less HNT over the same period of time. This may
seem counterintuitive. Shouldn't the blockchain produce more HNT when block
times are slower to ensure the
5,000,000 per month target is hit? No. Again,
think blocks, not clocks. Here's a step-by-step example to make it clearer:
- Let's assume for a given
60minute period, the average block time was
120seconds (which is double the target of
- This would mark
30blocks over the
60minute period, conclude an epoch, and result in HNT rewards being distributed.
- As with any epoch, we would distribute the target of (approximately)
- However, since this epoch took twice as long as normal -
30minute target - the blockchain essentially distributes HNT at half the normal rate.
When Block Times Slow Down, Everyone Earns Less
The most important take away here is that, when block times slow and HNT production is reduced, everyone participating in the Network - Witnesses, Challengers, Helium, Investors, etc. - is impacted equally (with the exception of Consensus Group members; more on this below). So, although it's annoying that the effective rate of HNT may have dropped over a given period of time, know that you're not the only one earning less. And this is by design.
Consensus Groups and Slow Block Times
The only group that doesn't see its HNT reduced per epoch when blocks are slow
is the Consensus Group. Currently there are 16 members of each Consensus Group,
sharing 6% of the HNT produced per epoch - or approximately
12.842475 HNT per
Consensus Group member.
This amount stays fixed while every other category of HNT payout is prorated so
that members of the Consensus Group are incentivized to keep elections fast.
Otherwise, a malicious Consensus Group member might be inclined to prolong
elections. This could be done, for example, to prevent a subsequent election,
thus ensuring current membership in the Consensus Group stays intact. By
distributing a fixed amount of HNT per
30 block epoch (as opposed to prorating
payouts), we remove the incentive to disrupt elections.