Cycles cost formulas
Canisters are charged for the resources they consume and any operations they perform using features such as HTTPS outcalls, threshold signatures, and the Bitcoin integration API. At a high level this can be visualized using the following diagram:
A detailed, mathematical example of how the cost of running a canister on a 13-node subnet is computed can be found on the wiki.
Specific mathematical formulas used for different types of costs can be found below for reference.
The price of cycles is fixed against the price of XDR, where 1 trillion cycles equals 1 XDR. As of December 18, 2023, the exchange rate for 1 XDR = $1.336610. The exchange rate for USD/XDR may vary. Learn more about XDR exchange rates.
The following table shows units of cycles and the respective fiat values:
| Abbreviation | Name | In numbers | Cycles XDR value | Cycles USD value |
|---|---|---|---|---|
| T | Trillion | 1_000_000_000_000 | 1 | 1.336610 |
| B | Billion | 1_000_000_000 | 0.001 | 0.001336610 |
| M | Million | 1_000_000 | 0.000001 | 0.000001336610 |
| k | Thousand | 1_000 | 0.000000001 | 0.000000001336610 |
Cost calculation formulas
A detailed, mathematical example of how the cost of running a canister on a 13-node subnet is computed can be found on the wiki.
Specific mathematical formulas used for different types of costs can be found below for reference.
Message transmissions
A fixed baseline fee and per-byte fee are charged for each byte of the message: base-fee + per-byte-fee * size-in-bytes.
Execution
The execution cost consists of a fixed execution fee and a per-instruction fee (on application subnets (13 nodes), 10 instructions cost 4 cycles) that is charged for each executed WebAssembly instruction:
base-fee + per-instruction-fee * number-of-instructions
The current values of fees are base-fee = 5M cycles (or $0.00000668305 USD), per-instruction-fee = 1 cycle (or $0.01325 USD for 1B instructions).
HTTPS outcalls
The cycles cost of an HTTPS outcall request has both a fixed and variable component. The fixed component accounts for the known overhead associated with an HTTPS outcall, whereas the variable component accounts for the resources consumed during the request. The cost scales with regard to subnet size.
Currently, these fees are:
total_fee = base_fee + size_fee
base_fee = (3_000_000 + 60_000 * n) * n
size_fee = (400 * request_bytes + 800 * max_response_bytes) * n
The request_bytes includes the entire request, not just the HTTP body:
request_size = url.len + transform.name.len + transform.context.len + body.len + header_len
header_len = header_1.name + header_1.value + ... + header_n.name + header_n.value
while max_response_bytes is either set by the canister or defaults to 2M.
Cycles price breakdown
The table below details the cost of compute, storage transmissions, and canister calls.
You can use the pricing calculator to estimate the cost for your dapp.
| Canister transmission | Description | Who is responsible for paying the cycles fee? | 13-node subnets cycles cost | 13-node subnets USD cost | 34-node subnets | 34-node subnets USD cost | |
|---|---|---|---|---|---|---|---|
| Query call | Query information from a canister. | N/A | Free | Free | Free | Free | |
| Canister creation | For creating canisters on a subnet. | Created canister | 500B | $0.668305000000 | 500B / 13 * 34 | $1.74787461538 | |
| Compute percent allocated per second | For each percent of the reserved compute allocation (a scarce resource). | Canister with allocation | 10M | $0.000013366100 | 10M / 13 * 34 | $0.000034957492 | |
| Update message execution | For every update message executed. | Target canister | 5M | $0.000006683050 | 5M / 13 * 34 | $0.000017478740 | |
| 1B executed instructions | For every 1B instructions executed when executing update type messages. | Canister executing instructions | 1B | $0.001336610000 | 1B / 13 * 34 | $0.003495749230 | |
| Xnet call | For every inter-canister call performed (includes the cost for sending the request and receiving the response). | Sending canister | 260K | $0.000000347519 | 260K / 13 * 34 | $0.000000908895 | |
| Xnet byte transmission | For every byte sent in an inter-canister call (for bytes sent in the request and response). | Sending canister | 1K | $0.000000001337 | 1K / 13 * 34 | $0.000000003496 | |
| Ingress message reception | For every ingress message received. | Receiving canister | 1.2M | $0.000001603932 | 1.2M / 13 * 34 | $0.000004194899 | |
| Ingress byte reception | For every byte received in an ingress message. | Receiving canister | 2K | $0.000000002673 | 2K / 13 * 34 | $0.000000006991 | |
| GiB storage per second | For storing a GiB of data per second. | Canister with storage | 127K | $0.000000169749 | 127K / 13 * 34 | $0.000000443960 | |
| HTTPS outcalls | |||||||
| HTTPS outcall (per call) | For sending an HTTPS outcall to a server outside the IC, per message (http_request). | Sending canister | 49_140_000 | $0.000065681015 | 171_360_000 | $0.000229041490 | |
| HTTPS outcall request message size (per byte) | For sending an HTTPS outcall to a server outside the IC, per request byte (http_request). | Sending canister | 5_200 | $0.000000006950 | 13_600 | $0.000000018178 | |
| HTTPS outcall response message size (per byte) | For sending an HTTPS outcall to a server outside the IC, per reserved response byte (http_request). | Sending canister | 10_400 | $0.000000013901 | 27_200 | $0.000000036356 |
The following table shows the calculated storage cost per GiB for a 30-day month:
| 13-node subnets | 34-node subnets | ||
|---|---|---|---|
| GiB Storage Per Month | For storing a GiB of data per month | $0.446150495 | $1.70 |