STACKS
Broadcast raw transactions on the network. You can use the @stacks/transactions project to generate a raw transaction payload.
GET fee estimates
POST /v2/transactions HTTP/1.1
Host: stacks.nownodes.io
Content-Type: application/octet-stream
Accept: */*
Content-Length: 379
"binary format of 00000000010400bed38c2aadffa348931bcb542880ff79d607afec000000000000000000000000000000c800012b0b1fff6cccd0974966dcd665835838f0985be508e1322e09fb3d751eca132c492bda720f9ef1768d14fdabed6127560ba52d5e3ac470dcb60b784e97dc88c9030200000000000516df0ba3e79792be7be5e50a370289accfc8c9e032000000000000303974657374206d656d6f00000000000000000000000000000000000000000000000000"e161978626f216b2141b156ade10501207ae535fa365a13ef5d7a7c9310a09f2Get contract interface using a contract_address and contract name
Stacks address
Contract name
The Stacks chain tip to query from. If tip == latest, the query will be run from the latest known tip (includes unconfirmed state).
GET /v2/contracts/interface/{contract_address}/{contract_name} HTTP/1.1
Host: stacks.nownodes.io
Accept: */*
Contract interface
{
"functions": [
{
"name": "get-value",
"access": "public",
"args": [
{
"name": "key",
"type": {
"buffer": {
"length": 32
}
}
}
],
"outputs": {
"type": {
"response": {
"ok": {
"buffer": {
"length": 32
}
},
"error": "int128"
}
}
}
},
{
"name": "set-value",
"access": "public",
"args": [
{
"name": "key",
"type": {
"buffer": {
"length": 32
}
}
},
{
"name": "value",
"type": {
"buffer": {
"length": 32
}
}
}
],
"outputs": {
"type": {
"response": {
"ok": "uint128",
"error": "none"
}
}
}
},
{
"name": "test-emit-event",
"access": "public",
"args": [],
"outputs": {
"type": {
"response": {
"ok": "uint128",
"error": "none"
}
}
}
},
{
"name": "test-event-types",
"access": "public",
"args": [],
"outputs": {
"type": {
"response": {
"ok": "uint128",
"error": "none"
}
}
}
}
],
"variables": [
{
"name": "recipient",
"type": "principal",
"access": "constant"
},
{
"name": "sender",
"type": "principal",
"access": "constant"
}
],
"maps": [
{
"name": "store",
"key": [
{
"name": "key",
"type": {
"buffer": {
"length": 32
}
}
}
],
"value": [
{
"name": "value",
"type": {
"buffer": {
"length": 32
}
}
}
]
}
],
"fungible_tokens": [
{
"name": "novel-token-19"
}
],
"non_fungible_tokens": [
{
"name": "hello-nft",
"type": "uint128"
}
]
}Attempt to fetch data from a contract data map. The contract is identified with [Stacks Address] and [Contract Name] in the URL path. The map is identified with [Map Name].
The key to lookup in the map is supplied via the POST body. This should be supplied as the hex string serialization of the key (which should be a Clarity value). Note, this is a JSON string atom.
In the response, data is the hex serialization of the map response. Note that map responses are Clarity option types, for non-existent values, this is a serialized none, and for all other responses, it is a serialized (some ...) object.
Stacks address
Contract name
Map name
Returns object without the proof field when set to 0
The Stacks chain tip to query from. If tip == latest, the query will be run from the latest known tip (includes unconfirmed state).
POST /v2/map_entry/{contract_address}/{contract_name}/{map_name} HTTP/1.1
Host: stacks.nownodes.io
Content-Type: application/json
Accept: */*
Content-Length: 6
"text"{
"data": "0x0a0c000000010a6d6f6e737465722d69640100000000000000000000000000000001",
"proof": "0x123..."
}Returns the Clarity source code of a given contract, along with the block height it was published in, and the MARF proof for the data
Stacks address
Contract name
Returns object without the proof field if set to 0
The Stacks chain tip to query from. If tip == latest, the query will be run from the latest known tip (includes unconfirmed state).
GET /v2/contracts/source/{contract_address}/{contract_name} HTTP/1.1
Host: stacks.nownodes.io
Accept: */*
Success
{
"source": "(define-constant sender 'SZ2J6ZY48GV1EZ5V2V5RB9MP66SW86PYKKQ9H6DPR)\n(define-constant recipient 'SM2J6ZY48GV1EZ5V2V5RB9MP66SW86PYKKQVX8X0G)\n\n(define-fungible-token novel-token-19)\n(begin (ft-mint? novel-token-19 u12 sender))\n(begin (ft-transfer? novel-token-19 u2 sender recipient))\n\n(define-non-fungible-token hello-nft uint)\n(begin (nft-mint? hello-nft u1 sender))\n(begin (nft-mint? hello-nft u2 sender))\n(begin (nft-transfer? hello-nft u1 sender recipient))\n\n(define-public (test-emit-event)\n (begin\n (print \"Event! Hello world\")\n (ok u1)))\n(begin (test-emit-event))\n\n(define-public (test-event-types)\n (begin\n (unwrap-panic (ft-mint? novel-token-19 u3 recipient))\n (unwrap-panic (nft-mint? hello-nft u2 recipient))\n (unwrap-panic (stx-transfer? u60 tx-sender 'SZ2J6ZY48GV1EZ5V2V5RB9MP66SW86PYKKQ9H6DPR))\n (unwrap-panic (stx-burn? u20 tx-sender))\n (ok u1)))\n\n(define-map store ((key (buff 32))) ((value (buff 32))))\n(define-public (get-value (key (buff 32)))\n (begin\n (match (map-get? store ((key key)))\n entry (ok (get value entry))\n (err 0))))\n(define-public (set-value (key (buff 32)) (value (buff 32)))\n (begin\n (map-set store ((key key)) ((value value)))\n (ok u1)))",
"publish_height": 3196,
"proof": "0000001104060000001ec4e..."
}Call a read-only public function on a given smart contract.
The smart contract and function are specified using the URL path. The arguments and the simulated tx-sender are supplied via the POST body in the following JSON format:
Stacks address
Contract name
Function name
The Stacks chain tip to query from. If tip == latest, the query will be run from the latest known tip (includes unconfirmed state).
Describes representation of a Type-0 Stacks 2.0 transaction. https://github.com/stacksgov/sips/blob/main/sips/sip-005/sip-005-blocks-and-transactions.md#type-0-transferring-an-asset
The simulated tx-sender
An array of hex serialized Clarity values
POST /v2/contracts/call-read/{contract_address}/{contract_name}/{function_name} HTTP/1.1
Host: stacks.nownodes.io
Content-Type: application/json
Accept: */*
Content-Length: 102
{
"sender": "SP31DA6FTSJX2WGTZ69SFY11BH51NZMB0ZW97B5P0.get-info",
"arguments": [
"0x0011...",
"0x00231..."
]
}Success
{
"okay": true,
"result": "0x111..."
}Get the account data for the provided principal
Where balance is the hex encoding of a unsigned 128-bit integer (big-endian), nonce is a unsigned 64-bit integer, and the proofs are provided as hex strings.
For non-existent accounts, this does not 404, rather it returns an object with balance and nonce of 0.
Stacks address or a Contract identifier (e.g. SP31DA6FTSJX2WGTZ69SFY11BH51NZMB0ZW97B5P0.get-info)
Returns object without the proof field if set to 0
The Stacks chain tip to query from. If tip == latest, the query will be run from the latest known tip (includes unconfirmed state).
GET /v2/accounts/{principal} HTTP/1.1
Host: stacks.nownodes.io
Accept: */*
Success
{
"balance": "0x0000000000000000000000000007a120",
"locked": "0x0000000000000000000000000007a120",
"unlock_height": 126,
"nonce": 2867,
"balance_proof": "0xabce",
"nonce_proof": "0xabcd"
}Get an estimated fee for the supplied transaction. This estimates the execution cost of the transaction, the current fee rate of the network, and returns estimates for fee amounts.
transaction_payloadis a hex-encoded serialization of the TransactionPayload for the transaction.estimated_lenis an optional argument that provides the endpoint with an estimation of the final length (in bytes) of the transaction, including any post-conditions and signatures
If the node cannot provide an estimate for the transaction (e.g., if the node has never seen a contract-call for the given contract and function) or if estimation is not configured on this node, a 400 response is returned. The 400 response will be a JSON error containing a reason field which can be one of the following:
DatabaseError- this Stacks node has had an internal database error while trying to estimate the costs of the supplied transaction.NoEstimateAvailable- this Stacks node has not seen this kind of contract-call before, and it cannot provide an estimate yet.CostEstimationDisabled- this Stacks node does not perform fee or cost estimation, and it cannot respond on this endpoint.
The 200 response contains the following data:
estimated_cost- the estimated multi-dimensional cost of executing the Clarity VM on the provided transaction.estimated_cost_scalar- a unitless integer that the Stacks node uses to compare how much of the block limit is consumed by different transactions. This value incorporates the estimated length of the transaction and the estimated execution cost of the transaction. The range of this integer may vary between different Stacks nodes. In order to compute an estimate of total fee amount for the transaction, this value is multiplied by the same Stacks node's estimated fee rate.cost_scalar_change_by_byte- a float value that indicates how much theestimated_cost_scalarvalue would increase for every additional byte in the final transaction.estimations- an array of estimated fee rates and total fees to pay in microSTX for the transaction. This array provides a range of estimates (default: 3) that may be used. Each element of the array contains the following fields:fee_rate- the estimated value for the current fee rates in the networkfee- the estimated value for the total fee in microSTX that the given transaction should pay. These values are the result of computing:fee_ratexestimated_cost_scalar. If the estimated fees are less than the minimum relay fee(1 ustx x estimated_len), then that minimum relay fee will be returned here instead.
Note: If the final transaction's byte size is larger than supplied to estimated_len, then applications should increase this fee amount by:
fee_rate x cost_scalar_change_by_byte x (final_size - estimated_size)
POST request for estimated fee
POST /v2/fees/transaction HTTP/1.1
Host: stacks.nownodes.io
Content-Type: application/json
Accept: */*
Content-Length: 140
{
"estimated_len": 350,
"transaction_payload": "021af942874ce525e87f21bbe8c121b12fac831d02f4086765742d696e666f0b7570646174652d696e666f00000000"
}Estimated fees for the transaction
{
"cost_scalar_change_by_byte": 0.00476837158203125,
"estimated_cost": {
"read_count": 19,
"read_length": 4814,
"runtime": 7175000,
"write_count": 2,
"write_length": 1020
},
"estimated_cost_scalar": 14,
"estimations": [
{
"fee": 17,
"fee_rate": 1.2410714285714286
},
{
"fee": 125,
"fee_rate": 8.958333333333332
},
{
"fee": 140,
"fee_rate": 10
}
]
}Get Core API information
GET /v2/info HTTP/1.1
Host: stacks.nownodes.io
Accept: */*
Success
{
"peer_version": 385875968,
"pox_consensus": "17f76e597bab45646956f38dd39573085d72cbc0",
"burn_block_height": 16,
"stable_pox_consensus": "8e0561978fc5506b68a589c402dad97e862edb59",
"stable_burn_block_height": 15,
"server_version": "blockstack-core 0.0.1 => 23.0.0.0 (, release build, linux [x86_64])",
"network_id": 2147483648,
"parent_network_id": 3669344250,
"stacks_tip_height": 15,
"stacks_tip": "b1807a2d3f7f8c7922f7c1d60d7c34145ade05d789640dc7dc9ec1021e07bb54",
"stacks_tip_consensus_hash": "17f76e597bab45646956f38dd39573085d72cbc0",
"unanchored_tip": "0000000000000000000000000000000000000000000000000000000000000000",
"tenure_height": 523,
"exit_at_block_height": null,
"is_fully_synced": false
}Get Proof of Transfer (PoX) information. Can be used for Stacking.
The Stacks chain tip to query from. If tip == latest, the query will be run from the latest known tip (includes unconfirmed state).
GET /v2/pox HTTP/1.1
Host: stacks.nownodes.io
Accept: */*
Success
{
"contract_id": "SP000000000000000000002Q6VF78.pox",
"pox_activation_threshold_ustx": 52329761604388,
"first_burnchain_block_height": 666050,
"current_burnchain_block_height": 812345,
"prepare_phase_block_length": 100,
"reward_phase_block_length": 2000,
"reward_slots": 4000,
"rejection_fraction": 25,
"total_liquid_supply_ustx": 1046595232087772,
"current_cycle": {
"id": 2,
"min_threshold_ustx": 70000000000,
"stacked_ustx": 202157971547640,
"is_pox_active": true
},
"next_cycle": {
"id": 3,
"min_threshold_ustx": 70000000000,
"min_increment_ustx": 52329761604,
"stacked_ustx": 162057034977640,
"prepare_phase_start_block_height": 672250,
"blocks_until_prepare_phase": 407,
"reward_phase_start_block_height": 672350,
"blocks_until_reward_phase": 507,
"ustx_until_pox_rejection": 261648808021925
},
"min_amount_ustx": 70000000000,
"prepare_cycle_length": 100,
"reward_cycle_id": 2,
"reward_cycle_length": 2100,
"rejection_votes_left_required": 261648808021925,
"next_reward_cycle_in": 507,
"contract_versions": [
{
"contract_id": "SP000000000000000000002Q6VF78.pox",
"activation_burnchain_block_height": 666050,
"first_reward_cycle_id": 0
},
{
"contract_id": "SP000000000000000000002Q6VF78.pox-2",
"activation_burnchain_block_height": 712345,
"first_reward_cycle_id": 123
}
]
}Determine whether or not a specified trait is implemented (either explicitly or implicitly) within a given contract.
Stacks address
Contract name
Trait Stacks address
Trait contract name
Trait name
The Stacks chain tip to query from. If tip == "latest", the query will be run from the latest known tip (includes unconfirmed state). If the tip is left unspecified, the stacks chain tip will be selected (only includes confirmed state).
GET /v2/traits/{contract_address}/{contract_name}/{trait_contract_address}/{trait_contract_name}/{trait_name} HTTP/1.1
Host: stacks.nownodes.io
Accept: */*
Success
{
"is_implemented": true
}Attempt to fetch the value of a MARF key.
In the response, data is the hex serialization of the value.
MARF key
Returns object without the proof field when set to 0
The Stacks chain tip to query from. If tip == latest, the query will be run from the latest known tip (includes unconfirmed state).
POST /v2/clarity/marf/{clarity_marf_key} HTTP/1.1
Host: stacks.nownodes.io
Accept: */*
{
"data": "0x0a0c000000010a6d6f6e737465722d69640100000000000000000000000000000001",
"proof": "0x123..."
}Attempt to fetch the metadata of a contract. The contract is identified with [Contract Address] and [Contract Name] in the URL path. The metadata key is identified with [Clarity Metadata Key].
In the response, data is formatted as JSON.
Stacks address
Contract name
Metadata key
The Stacks chain tip to query from. If tip == latest, the query will be run from the latest known tip (includes unconfirmed state).
POST /v2/clarity/metadata/{contract_address}/{contract_name}/{clarity_metadata_key} HTTP/1.1
Host: stacks.nownodes.io
Accept: */*
{
"data": "'{\"contract_identifier\":{...}, \"private_function_types\":{...}'"
}Attempt to fetch the value of a constant inside a contract. The contract is identified with [Stacks Address] and [Contract Name] in the URL path. The constant is identified with [Constant Name].
In the response, data is the hex serialization of the constant value.
Stacks address
Contract name
Constant name
The Stacks chain tip to query from. If tip == latest, the query will be run from the latest known tip (includes unconfirmed state).
POST /v2/constant_val/{contract_address}/{contract_name}/{constant_name} HTTP/1.1
Host: stacks.nownodes.io
Accept: */*
{
"data": "0x01ce..."
}Used by stackers to validate a proposed Stacks block from a miner.
This API endpoint requires a basic Authorization header.
POST /v3/block_proposal HTTP/1.1
Host: stacks.nownodes.io
Content-Type: application/json
Accept: */*
Content-Length: 928
{
"block": "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",
"chain_id": 2147483648
}{
"message": "Block proposal is processing, result will be returned via the event observer",
"result": "Accepted"
}Used to get stacker and signer set information for a given cycle.
This will only return information for cycles started in Epoch-2.5 where PoX-4 was active and subsequent cycles.
reward cycle number
GET /v3/stacker_set/{cycle_number} HTTP/1.1
Host: stacks.nownodes.io
Accept: */*
{
"stacker_set": {
"rewarded_addresses": [
{
"Standard": [
{
"bytes": "dc5f18421006ee2b98ab972edfa7268a981e3f00",
"version": 26
},
"SerializeP2PKH"
]
}
],
"signers": [
{
"signing_key": "02d0a27e4f1bf186b4391eecfcc4d4a0d403684ad089b477b8548a69dd6378bf26",
"slots": 1,
"stacked_amt": 2143020000000000
}
],
"start_cycle_state": {
"missed_reward_slots": []
}
}
}Fetch a Nakamoto block by its index block hash.
The block's ID hash
GET fee estimates
GET /v3/blocks/{block_id} HTTP/1.1
Host: stacks.nownodes.io
Accept: */*
binaryFetch a Nakamoto block by its height and optional tip.
The block's height
The Stacks chain tip to query from. If tip == latest or empty, the query will be run from the latest known tip.
GET fee estimates
GET /v3/blocks/height/{block_height} HTTP/1.1
Host: stacks.nownodes.io
Accept: */*
binaryFetch metadata about the ongoing Nakamoto tenure. This information is sufficient to obtain and authenticate the highest complete tenure, as well as obtain new tenure blocks.
GET /v3/tenures/info HTTP/1.1
Host: stacks.nownodes.io
Accept: */*
Metadata about the ongoing tenure
{
"consensus_hash": "4c5a49be0e34dc603b66f090fd07d28a2f76a2ad",
"parent_consensus_hash": "fa8a04af41957499afdd4082b9b702ffca9a4370",
"parent_tenure_start_block_id": "0cfec8433849d353ad6b2fe1173da143e3d4a3ab452588a14eb074d0181ac202",
"reward_cycle": 8,
"tenure_start_block_id": "0425099d51547c714df6a7864c040c1a605b198ff07f71d19a823139c88a35f8",
"tip_block_id": "52d64f5e47abc7666c4fed3fe850f381f93f2d588ee2a92a4e07b44f14588d5e",
"tip_height": 416
}Fetch a sequence of Nakamoto blocks in a tenure. The blocks will be served in order from highest to lowest. The blocks will be encoded in their SIP-003 wire format, and concatenated together.
The tenure-start block ID of the tenure to query
The block ID hash of the highest block in this tenure that is already known to the caller. Neither the corresponding block nor any of its ancestors will be served. This is used to fetch tenure blocks that the caller does not have.
GET fee estimates
GET /v3/tenures/{block_id} HTTP/1.1
Host: stacks.nownodes.io
Accept: */*
SIP-003-encoded Nakamoto blocks, concatenated together
binaryFetch sortition information about a burnchain block. If the lookup_kind and lookup parameters are empty, it will return information about the latest burn block.
The style of lookup that should be performed. If not given, the most recent burn block processed will be returned.
Otherwise, the lookup_kind should be one of the following strings:
consensus- find the burn block using the consensus hash supplied in thelookupfield.burn_height- find the burn block using the burn block height supplied in thelookupfield.burn- find the burn block using the burn block hash supplied in thelookupfield.latest_and_last- return information about the latest burn block with a winning miner and the previous such burn block
The value to use for the lookup if lookup_kind is consensus, burn_height, or burn
GET /v3/sortitions/{lookup_kind}/{lookup} HTTP/1.1
Host: stacks.nownodes.io
Accept: */*
Information for the burn block or in the case of latest_and_last, multiple burn blocks
[
{
"burn_block_hash": "0x046f54cd1924a5d80fc3b8186d0334b7521acae90f9e136e2bee680c720d0e83",
"burn_block_height": 231,
"burn_header_timestamp": 1726797570,
"sortition_id": "0x8a5116b7b4306dc4f6db290d1adfff9e1347f3e921bb793fc4c33e2ff05056e2",
"parent_sortition_id": "0xdaf479110cf859e58c56b6ae941f8a14e7c7992c57027183dfbda4a4b820897c",
"consensus_hash": "0x8d2c51db737597a93191f49bcdc9c7bb44b90892",
"was_sortition": true,
"miner_pk_hash160": "0x6bc51b33e9f3626944eb879147e18111581f8f9b",
"stacks_parent_ch": "0x697357c72da55b759b1d6b721676c92c69f0b490",
"last_sortition_ch": "0x697357c72da55b759b1d6b721676c92c69f0b490",
"committed_block_hash": "0xeea47d6d639c565027110e192e308fb11656183d5c077bcd718d830652800183",
"vrf_seed": "0x48b754acc291a5bfad1354ee19bbc471f14af2b21dc7eccc0f929bd16798defe"
}
]Get number of blocks signed by signer during a given reward cycle
Hex-encoded compressed Secp256k1 public key of signer
Reward cycle number
GET /v3/signer/{signer}/{cycle_number} HTTP/1.1
Host: stacks.nownodes.io
Accept: */*
Number of blocks signed
7Get number of blocks signed by signer during a given reward cycle
Hex-encoded compressed Secp256k1 public key of signer
Reward cycle number
GET /v3/signer/{signer}/{cycle_number} HTTP/1.1
Host: stacks.nownodes.io
Accept: */*
Number of blocks signed
7Last updated