substrate-js-utils

A set of useful JavaScript utilities for Substrate that uses the Polkadot{JS} API; Also deployed as a website.

Package 31 stars GitHub

Substrate JS Utilities

A collection of browser-based utilities for working with Substrate and Polkadot data. No build step required — just static HTML and JavaScript.

String to Hex — Bidirectional string/hex conversion
Balance to Hex — Number to little-endian hex conversion
AccountId to Hex — SS58 address to raw hex bytes
Blake2 Hash — Blake2b hashing with configurable bit length
Blake2 Concat — Blake2b hash concatenated with input
XXHash — TwoX hashing with configurable bit length
XXHash Concat — TwoX hash concatenated with input
Seed to Address — Generate SS58 address from a seed phrase
Change Address Prefix — Convert addresses between network prefixes
Module ID to Address — Convert a pallet ID to its sovereign account
Pallet ID Sub-Account — Derive pallet sub-accounts from a pallet ID and index
Para ID to Address — Derive parachain sovereign accounts (child or sibling)
Sub-Account Generator — Derive Utility pallet sub-accounts
Ethereum to Substrate Address — Bidirectional ETH/Substrate address conversion
u8a Array to Hex — Convert byte arrays to hex and back
Number to Hex — Configurable bit length, endianness, and SCALE compact encoding

SCALE Decoder — Decode raw SCALE-encoded hex bytes with custom type definitions
Query Indices — Batch query account indices from a live chain
Network Versions — Query runtime versions across multiple networks
Query Nominations — View staking nominations and estimate rewards
Event Counter — Count and graph blockchain events across block ranges

No build step needed. The site runs as static files with dependencies loaded via CDN.

npm install
npm test

Tests use Node's built-in test runner and cover all utility logic (SCALE encoding/decoding, address derivation, hashing, conversions, etc.).