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formatter
converter
- converter
Base64 Encoder / Decoder
Encode text or files to Base64, or decode Base64 back to text or a downloadable file — instantly, entirely in your browser.
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Timestamp / Unix Time Converter
Convert Unix timestamps to readable dates and back, in one input.
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JSON to TypeScript Converter
Paste JSON and instantly generate TypeScript interfaces or types.
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Cron Expression Generator
Build a cron expression visually, or paste one in to see what it means in plain English.
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Prisma Schema ↔ SQL DDL Converter
Convert between Prisma schema and MySQL/PostgreSQL DDL, including relations, enums, and indexes.
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generator
decoder
web3
- web3
ABI Decoder & Encoder
Decode calldata and event logs, or encode function calls, using any contract ABI.
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Ethereum / EVM Unit Converter
Convert between Wei, Gwei, and Ether, and estimate gas fees for legacy or EIP-1559 transactions.
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Smart Account (ERC-4337) UserOp Builder
Build an ERC-4337 UserOperation for EntryPoint v0.6 or v0.7 and see its JSON, packed encoding, and UserOpHash.
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