> ## Documentation Index > Fetch the complete documentation index at: https://sure-917046f5-mintlify-docs-update-1787543210181.mintlify.site/llms.txt > Use this file to discover all available pages before exploring further. # On-chain wallets > Track self-custody Bitcoin, EVM, and Solana wallets by public address Sure can track wallets you hold the keys to — Bitcoin, six EVM networks, and Solana — from their **public addresses only**. Nothing is signed, no key or seed phrase is ever entered, and no API key is required for any chain. ## How it works When you link a wallet address, Sure: * Creates one account per **asset**, per **address**, per **network** — a wallet holding ETH and USDC on Ethereum becomes two accounts, both Crypto accounts with the "wallet" subtype * Records the **quantity** held, read from the chain * Creates a **holding** valued at the current price, or at zero when no price is available * Imports **transfers** in and out as investment trades when the price for that day is known, so cost basis and the value chart reconstruct back to acquisition Balances are read-only and always derived from the chain. Editing them by hand is pointless: the next sync overwrites them. ## Supported networks | Network | Data source | | -------- | ----------------------------------------------- | | Bitcoin | [mempool.space](https://mempool.space) REST API | | Ethereum | Blockscout (`eth.blockscout.com`) | | Base | Blockscout (`base.blockscout.com`) | | Arbitrum | Blockscout (`arbitrum.blockscout.com`) | | Optimism | Blockscout (`optimism.blockscout.com`) | | Polygon | Blockscout (`polygon.blockscout.com`) | | Gnosis | Blockscout (`gnosis.blockscout.com`) | | Solana | Public JSON-RPC (`api.mainnet-beta.solana.com`) | ## Setting up on-chain wallets Before linking a wallet, make sure a crypto-capable market data provider is enabled. Without one, every wallet is tracked by quantity and **valued at zero**. On a self-hosted instance, go to **Settings → Self-Hosting → Market data providers** and enable `binance_public` (keyless). You can also set `SECURITIES_PROVIDERS` to a comma-separated list that includes `binance_public`. If your family currency is not USD, you also need an exchange rate provider. `frankfurter` requires no API key and can be set via `EXCHANGE_RATE_PROVIDER=frankfurter`. Go to **Settings → Providers → On-chain wallets → Add wallet**. 1. Paste the public address. Leave the network on "Detect automatically" unless you know which one you want. 2. If the address format matches several networks — every `0x` address is valid on all six EVM networks — Sure probes each and asks you to choose, marking the ones where it found activity. 3. Pick the assets to track. The native coin and assets the data source treats as notable are pre-ticked. "Notable" means a priced holding worth more than a dollar on EVM networks, or a place on Solana's verified token list. You can still track anything listed; unpriceable assets show a quantity and a value of zero. Nothing is imported that you did not tick. ## Managing a wallet Go to **Settings → Providers → On-chain wallets → Manage wallets**. * **Review tokens** — reopens the asset selection with the address unchanged. Use this to start tracking a token that arrived later, or stop tracking one you no longer want. * **Stop tracking** (per asset) — drops one asset. * **Change address** — corrects the address while keeping the accounts, holdings, and balance history attached to it. * **Disconnect wallet** — drops every asset at one address. Disconnecting never deletes an account. The provider link is removed, holdings are detached, and the account stays as a manual account that no longer updates. Delete the account itself if you want it gone. An address can only be tracked once per network. To change which assets are tracked, use **Review tokens** rather than adding the address again. ## Pricing On-chain data sources report quantities, not values. Prices come from Sure's market data providers, and the only provider that can quote bare crypto symbols is **Binance public** (keyless). **Only tokens the crypto price provider quotes get a value, and it quotes by symbol.** A symbol is not a token's identity — its contract is. In practice the provider covers major assets and little else. Native coins (BTC, ETH, SOL, POL, XDAI) and large-cap tokens are the well-covered case. A zero next to a token you know is worth something almost always means the provider does not list that token, not that the balance is wrong. ## Limitations * **DeFi positions are not seen.** Staked ETH, liquidity-pool tokens, lending positions, and Solana stake accounts are invisible. Only natively-held coins and fungible tokens sitting at the address are read. * **Bitcoin is one address at a time.** Extended keys (`xpub`, `ypub`, `zpub`) are not supported. Most Bitcoin wallets are HD wallets where one extended key derives thousands of addresses — tracking a single address reports only that address's balance. * **Solana token names depend on a token list.** Names come from Jupiter's token search, and only for mints it reports as *verified*. Unverified or unknown mints keep a label built from the mint address and are tracked by quantity only. * **NFTs are not tracked.** They are filtered out by token standard. * **Fees are not itemised.** Network fees are included in the net effect of each transfer. * **Bridged assets are normalised.** USDC.e, USDbC, WETH, and similar 1:1-redeemable forms are tracked as their canonical asset. * **History is capped.** By default, up to 10 pages of transfer history are read per sync. Wallets with more history keep their current balance correct — balances come from an address summary, never from history — but their oldest transfers may not be imported. ## Self-hosting configuration All default endpoints are free and shared. You can override any of them with your own instance or a paid endpoint: | Variable | Default | | -------------------------------- | ------------------------------------- | | `MEMPOOL_SPACE_URL` | `https://mempool.space` | | `BLOCKSCOUT_ETHEREUM_URL` | `https://eth.blockscout.com` | | `BLOCKSCOUT_BASE_URL` | `https://base.blockscout.com` | | `BLOCKSCOUT_ARBITRUM_URL` | `https://arbitrum.blockscout.com` | | `BLOCKSCOUT_OPTIMISM_URL` | `https://optimism.blockscout.com` | | `BLOCKSCOUT_POLYGON_URL` | `https://polygon.blockscout.com` | | `BLOCKSCOUT_GNOSIS_URL` | `https://gnosis.blockscout.com` | | `SOLANA_RPC_URL` | `https://api.mainnet-beta.solana.com` | | `SOLANA_TOKEN_LIST_URL` | `https://lite-api.jup.ag` | | `ONCHAIN_HISTORY_MAX_PAGES` | `10` (max 200) | | `ONCHAIN_MAX_TOKENS_PER_ADDRESS` | `200` (max 5,000) | | `ONCHAIN_DETECTION_TIMEOUT` | `10` (seconds) | ### Optional Etherscan key Ethereum, and only Ethereum, can use Etherscan for transfer history instead of Blockscout. A key buys nothing except a higher rate limit. Add it under **Settings → Providers → On-chain wallets → Advanced**; it is stored encrypted, per family. A key only moves **transfer history** onto Etherscan. Balances and network detection always come from the keyless indexer. ## Troubleshooting **Every wallet shows a value of zero.** Either no crypto-capable market data provider is enabled, or your family currency is not USD and no exchange rate provider is configured. See [Pricing](#pricing) above. **One token shows zero while the others are fine.** The price provider does not quote that token. Pricing is by symbol and covers major assets — long-tail tokens are tracked by quantity and valued at zero. **A Bitcoin balance is much lower than my wallet app shows.** You are tracking one address of an HD wallet. See [Limitations](#limitations). **Sync says the explorer could not be reached.** The public endpoint is down, throttling you, or too slow to answer. Retry later, or point the relevant `*_URL` override at your own instance. **Solana shows balances but no transfers.** The free endpoint throttles the history methods; balances are kept and the history is marked incomplete. Set `SOLANA_RPC_URL` to your own node or a paid endpoint. **A token I received is not showing up.** New assets are never imported automatically. Use **Review tokens** and tick it. **Transfers appear with a value of 0 and are excluded from totals.** No price was available for that date yet. Once market data covers the range, the next sync upgrades those entries to trades automatically. **Manage wallets says the history is incomplete.** The address has more transfers than one sync reads. Raise `ONCHAIN_HISTORY_MAX_PAGES` if you need the full history and can afford the extra requests.