# DUST-20 Protocol — Universe Inscribe Documentation

> Published by Bitcoin Universe. Human docs: frontend/docs/dust-20/index.html
> Legacy GitBook (deprecated): https://dust-20.gitbook.io/dust20

## Summary

DUST-20 is a Bitcoin-native fungibility experiment. Token units are represented by dyed satoshis locked in UTXOs at the dust limit (546 sats per unit by default). Balances are tracked by aggregating colored UTXOs — transfer inscriptions are not required.

## Operations

- deploy — define tick, supply, unit_sats, max_sats
- mint — inscribe JSON with amt and sats padding (sats = amt × unit_sats)
- transfer — Bitcoin TX splitting dyed UTXO outputs; fees paid from non-colored UTXO

## Key rules

1. Mint inscription output value MUST equal the `sats` field (amt × unit_sats).
2. unit_sats is typically 546 (Bitcoin dust limit).
3. lim_sats (optional deploy field) caps max sats per mint inscription (e.g. UniSat 50,000 sat limit → amt × unit_sats ≤ lim_sats).
4. Transfer example: 91-token UTXO with 49,686 sats → send 5,460 sats (10×546) to receiver, change 44,226 to self.

## Deploy example

```json
{
  "p": "dust-20",
  "op": "deploy",
  "tick": "dust",
  "supply": "1000000",
  "unit_sats": "546",
  "max_sats": "546000000"
}
```

## Mint example (UniSat 50k padding cap)

```json
{
  "p": "dust-20",
  "op": "mint",
  "tick": "dust",
  "amt": "91",
  "sats": "49686"
}
```

## Tools

- Universe Inscribe: https://inscribe.bitcoinuniverse.io
- Indexer: https://tapwallet.io/index
- Deploy / Mint UI: https://tapwallet.io/inscribe/dust20
- OG pass (0-fee ops): https://tapwallet.io/launchpad
- X: https://x.com/pinkbtcuniverse

## Pages

- index.html — full protocol documentation (design system: Universe orange #FF9500, pink #FF0066)