Free tool
This Token-2022 extension planner turns a list of mint extensions into exact account sizes. Tick the extensions you want, see which ones every holder account inherits, and read the rent for the mint and for your holders in SOL and USD from live mainnet numbers.
No sign-up. Runs in your browser. Last reviewed by the Builderz team.
Fetching live mainnet numbers...
Step 1
Step 2
Locked rows come from your mint choices. Every holder account inherits them.
Result
Mint size
82 bytes
Holder account size
165 bytes
Rent basis: fallback, chain unreachable: (bytes + 128) x 6,960 lamports. SOL price unavailable, so USD is not shown.
Compared with a plain SPL mint (82 bytes, 0.001462 SOL) this mint is 0 bytes larger. Compared with a plain SPL token account (165 bytes, 0.002039 SOL) each holder account is 0 bytes larger.
Most extensions must be set before the mint is initialized. Plan the list now, because you cannot add them to a live mint later.
Sizes verified 2026-11-04 against https://github.com/solana-program/token-2022/tree/main/interface/src/extension
A token account starts at 165 bytes. With any extension, one account-type byte follows, then each extension adds a 2-byte type, a 2-byte length, and its body. If the total lands on 355 bytes, the multisig length, the program adds 2 bytes so the two cannot be confused.
A plain mint is 82 bytes. Once a mint has any extension, it is zero-padded to 165 bytes so the account-type byte sits at the same offset for mints and token accounts. A mint with only a metadata pointer is 234 bytes: 165, 1, then 4 plus 64.
Some mint extensions need a matching extension on every token account: transfer fee, transfer hook, pausable, non-transferable, and the confidential ones. Those rows are locked in step 2. Immutable owner, required memo, and CPI guard are optional and each holder account pays for them.
Token metadata is stored on the mint. It holds an update authority and a mint address (32 bytes each), then name, symbol, and URI as length-prefixed strings with 4 bytes of prefix each, then a 4-byte count and the extra key-value pairs. Every character is one byte of rent.
It does not create a mint, sign anything, or call an RPC for your accounts. It also does not advise on authorities or which extensions your product should use. It sizes the choices you make and prices them.
Most extensions must be set before the mint is initialized. Treat the mint-level extensions in this planner as fixed at creation. Some account-level extensions, such as required memo and CPI guard, can be enabled on an existing token account. Check the extension docs for the one you need.
The associated token account program sets the immutable owner extension. That is 165 base bytes, 1 account-type byte, and a 4-byte header with an empty body. Tick immutable owner here to see it.
No. The on-chain amount does not change. The extension stores a rate and a timestamp, and clients use them to show a scaled amount. Anything that reads the raw balance sees the same number as before.
The confidential transfer fee extension needs the confidential transfer extension on the same mint. Non-transferable tokens cannot move, so a transfer hook or a transfer fee on them never runs. The program rejects some combinations at initialization, so test your list on devnet.
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