ChangeNOW API
Official vendor OpenAPI document · agent-readyFinanceBankingapiKey8 EndpointsREST
For Agents
Quote and execute non-custodial cryptocurrency swaps across hundreds of trading pairs without requiring user registration. Useful for wallets, bots, and agents that need to convert between digital assets on demand.
Use for: I want to swap 0.1 BTC to ETH at the current rate, Get an estimate for converting USDT to SOL, Find the minimum amount required to exchange LTC to XRP, List all cryptocurrencies supported by ChangeNOW
Not supported: Does not handle custody, fiat banking rails, leveraged trading, or order books - use for non-custodial crypto-to-crypto swaps only.
ChangeNOW is an instant cryptocurrency exchange that lets users swap between hundreds of digital assets without creating an account. The v2 API provides programmatic access to the full exchange flow: listing supported currencies and trading pairs, fetching estimated swap amounts, retrieving minimum and range limits for a pair, creating an exchange transaction, and tracking its status by ID. It is commonly used by wallets, portfolio trackers, and crypto-aware agents that need to surface or execute non-custodial swaps.
Install Jentic One Beta
Connect the ChangeNOW API to your agent
Jentic One is a self-hosted execution layer for AI agents. It lets your agent call the ChangeNOW API, or any other public or private API you need. You set the rules, the agent never sees your credentials, and every call is logged.
Two steps, two machines. Install the instance in a safe environment, then register your agent from wherever it runs.
1
Step 1: Jentic One Host machine
# On the machine that will host your Jentic One instance:
curl -fsSL "https://jentic.com/install.sh?src=apis&api=%2Fapis%2Fchangenow.io%2Fchangenow" | sh2
Step 2: Agent machine
# On the machine where your agent runs (keep this separate from the instance):
curl -fsSL "https://jentic.com/install.sh?src=apis&api=%2Fapis%2Fchangenow.io%2Fchangenow" | sh
jentic register # connects your agent to your Jentic One instanceJentic One is in public beta. The setup above keeps your agent separate from the instance, which is what you want before using real credentials: an agent running as the same OS user as Jentic One can read its stored keys directly. Just evaluating? A single local install is fine to start. See the secure deployment guide for the tiers.
Capabilities
What an agent can do with ChangeNOW API.
List every supported cryptocurrency and fiat with availability flags via /exchange/currencies and /fiat-currencies/fiat
Quote an estimated receive amount for a swap pair before the user commits with /exchange/estimated-amount
Fetch the minimum exchange amount for a specific from/to pair using /exchange/min-amount
Retrieve the supported send-amount range for a pair to validate user input via /exchange/range
Create a non-custodial exchange transaction with payout address and refund address through POST /exchange
Track the lifecycle of a swap (waiting, confirming, exchanging, sending, finished) by transaction ID with /exchange/by-id
List all currently available trading pairs from /exchange/market-info/available-pairs
Use Cases
Patterns agents use ChangeNOW API for, with concrete tasks.
★ In-Wallet Crypto Swaps
Non-custodial wallets can offer in-app token swaps without holding user funds by integrating the ChangeNOW exchange flow. The wallet quotes a rate via /exchange/estimated-amount, validates limits via /exchange/range, and creates the swap with POST /exchange. Users send funds to the returned deposit address and ChangeNOW handles the conversion and payout to the user's destination wallet.
Quote a swap of 0.05 BTC to ETH, create the exchange with the user's ETH payout address, and return the BTC deposit address to the wallet UI
Portfolio Rebalancing Bots
Trading bots and portfolio managers can rebalance cross-chain holdings by chaining quotes and exchanges through the ChangeNOW API. The bot pulls /exchange/estimated-amount for each leg, validates against /exchange/min-amount and /exchange/range, then submits POST /exchange transactions for assets that need to be reallocated. Status polling via /exchange/by-id confirms completion before the next leg fires.
Quote SOL to USDT and ETH to USDT, create both exchanges if estimates clear thresholds, and poll /exchange/by-id until both finish
Price Comparison and Quote Aggregation
Aggregator sites and Telegram or Discord bots show users the best available rate across exchanges. Pulling /exchange/estimated-amount and /exchange/currencies from ChangeNOW gives a no-KYC quote that can be compared against other venues. The /exchange/market-info/available-pairs endpoint helps the aggregator pre-filter pairs that ChangeNOW actually supports.
Fetch estimated-amount for 1 ETH to USDT from ChangeNOW and surface the rate alongside other quoted venues for the user
Agent-Driven Crypto Conversions via Jentic
An AI agent given an instruction like 'swap 200 dollars worth of LTC to BTC' can resolve the entire flow through Jentic. It searches for the swap operation, pulls a fresh estimate, creates the exchange transaction, and returns the deposit address - all without seeing the API key. Jentic's your Jentic One instance keeps the ChangeNOW credential isolated.
Search Jentic for 'create a cryptocurrency exchange', estimate LTC to BTC, and create the swap with the user's BTC payout address
Key Endpoints
8 endpoints — changenow is an instant cryptocurrency exchange that lets users swap between hundreds of digital assets without creating an account.
METHOD
PATH
DESCRIPTION
GET
/exchange/currencies
List all supported cryptocurrencies
GET
/exchange/estimated-amount
Quote an estimated receive amount for a swap pair
GET
/exchange/min-amount
Get the minimum send amount for a pair
GET
/exchange/range
Get the supported send-amount range for a pair
POST
/exchange
Create a non-custodial exchange transaction
GET
/exchange/by-id
Look up exchange status and details by ID
GET
/exchange/market-info/available-pairs
List all currently tradable pairs
GET
/exchange/currencies
List all supported cryptocurrencies
GET
/exchange/estimated-amount
Quote an estimated receive amount for a swap pair
GET
/exchange/min-amount
Get the minimum send amount for a pair
GET
/exchange/range
Get the supported send-amount range for a pair
POST
/exchange
Create a non-custodial exchange transaction
GET
/exchange/by-id
Look up exchange status and details by ID
GET
/exchange/market-info/available-pairs
List all currently tradable pairs
Why Jentic?
What agents get from Jentic-routed access to this vendor.
Setup
Wiring ChangeNOW by hand means learning its x-changenow-api-key header auth, targeting the v2 host, and attaching the key to every quote and swap call yourself. Through Jentic you install once, import ChangeNOW from the API Directory, store the key once, and your agent calls it.
Permission scoping
ChangeNOW quotes and creates swaps through flat operation paths rather than a per-resource URL, so limit the agent to the operations it needs, such as estimating an amount and creating an exchange. You choose which operations it may call, so anything beyond quoting and non-custodial swaps is not included unless you add it.
Credential isolation
Your ChangeNOW API key is stored once, encrypted, by your own Jentic One instance and injected into the x-changenow-api-key header at execution time. It never enters the agent's prompt, logs, or context.
Intent-based discovery
Agents search Jentic by intent such as 'swap one cryptocurrency for another' or 'quote a crypto exchange rate', and Jentic returns the matching ChangeNOW operation with its input schema so the agent calls the right endpoint without browsing the reference docs.
Related APIs
Alternatives and complements available in the Jentic catalogue.
FAQs
Specific to using ChangeNOW API through Jentic.
What authentication does the ChangeNOW API use?
ChangeNOW uses an API key passed in the x-changenow-api-key header. When called through Jentic, the key is held in your Jentic One instance and the agent receives a scoped execution token rather than the raw key.
Can I create a swap without registering users on ChangeNOW?
Yes. ChangeNOW is fully non-custodial and does not require user accounts. POST /exchange takes the from/to currencies, send amount, and the user's payout address; ChangeNOW returns a deposit address that the user funds, and the swap completes automatically.
How do I quote an exchange rate before creating a transaction?
Call GET /exchange/estimated-amount with the from/to currencies and the send amount. The response includes the expected receive amount and helps your UI show the user a quote. Always re-validate with /exchange/min-amount and /exchange/range before submission.
What are the rate limits for the ChangeNOW API?
ChangeNOW does not publish a single fixed rate limit; production limits scale with your partner key. Implement backoff on HTTP 429 responses and cache the /exchange/currencies and /exchange/market-info/available-pairs lookups since they change rarely.
How do I track the status of a swap through Jentic?
After creating the exchange, call GET /exchange/by-id with the transaction ID. Through Jentic, search for 'check exchange status', load the schema, and execute. Run Jentic One, the self-hosted execution layer, for an agent API key.
Does ChangeNOW support fiat-to-crypto conversions?
The v2 API exposes a /fiat-currencies/fiat endpoint listing supported fiat options. Fiat purchase flows are handled by ChangeNOW's partner providers; the core /exchange operations remain crypto-to-crypto and require an existing crypto deposit.
Can I limit what my agent is allowed to do with the ChangeNOW API?
Yes. ChangeNOW exposes flat operation paths rather than per-resource URLs, so with your self-hosted Jentic One instance you decide which of its operations the agent may call and which credential it uses. You can allow only the calls you need, such as GET /exchange/estimated-amount to quote a rate and POST /exchange to create a non-custodial swap, while withholding others. Anything beyond the operations you grant, including creating exchanges, is not available to the agent unless your own rules permit it.
GET STARTED