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formatter
tester
- tester
Regex Tester & Explainer
Test regular expressions against sample text with live match highlighting, and get a plain-English breakdown of what the pattern actually does.
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Text Diff Checker
Compare two blocks of text side by side or unified, with word-level highlighting inside changed lines, whitespace/case-insensitive options, and a copyable unified diff.
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JSON Diff Checker
Compare two JSON documents structurally — ignores key order, highlights real value changes in a tree, and exports a JSON Patch (RFC 6902).
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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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Search Filter Query Builder
Build search filter conditions visually and get the exact syntax for Meilisearch, Algolia, Elasticsearch, and Typesense.
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CSV ↔ JSON Converter
Convert between CSV and JSON, with automatic type inference and a choice of comma, tab, or semicolon delimiters.
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YAML ↔ JSON Converter
Convert between YAML and JSON, with automatic type inference and support for nested objects and arrays.
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XML ↔ JSON Converter
Convert between XML and JSON, with automatic attribute handling and array detection for repeated elements.
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JWK ↔ PEM Converter
Convert RSA and EC keys between JWK (JSON Web Key) and PEM format entirely in your browser, with an RFC 7638 thumbprint shown for every key.
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Number Base Converter
Convert integers between decimal, hexadecimal, octal, and binary, live, with support for negative values and 0x/0o/0b prefixes.
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generator
- generator
UUID Generator
Generate RFC 9562-compliant UUID v4 (random) or v7 (time-ordered) values in bulk, entirely in your browser.
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Hash Generator
Generate MD5, SHA-1, SHA-256, and SHA-512 hashes or HMACs from text or files, entirely in your browser.
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QR Code Generator
Generate custom QR codes for URLs, WiFi, contacts, and more — plus batch-generate and decode QR images, free and entirely in your browser.
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JSON Schema Mock & Validator (Redis Pub/Sub)
Define a JSON Schema per event, generate realistic mock payloads, and validate real messages against it — with Redis Pub/Sub presets and a ready-to-run redis-cli PUBLISH output, all in your browser.
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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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LayerZero Chain ID / Endpoint ID (EID) Converter
Look up any LayerZero V2 chain by name, EVM chain ID, or Endpoint ID (eid), and get its matching chain ID, eid, and EndpointV2 contract address — ready to copy. Covers LayerZero V2's EVM mainnet and testnet deployments.
Open tool - web3
LayerZero OApp Options (Executor Options) Builder
Build and decode LayerZero V2 executor options bytes — lzReceive gas, native drop, lzCompose gas, and ordered execution — for use with send() or setEnforcedOptions().
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LayerZero Peer Address ↔ bytes32 Converter
Convert an EVM address to and from the left-zero-padded bytes32 form LayerZero V2's setPeer(uint32,bytes32) requires, and generate the ready-to-use setPeer calldata — with eid lookup by chain name, chain ID, or eid.
Open tool - web3
LayerZero V2 Raw Packet Decoder
Decode a raw LayerZero V2 packet — the encodedPayload bytes from a PacketSent event, or copied from LayerZero Scan — into its version, nonce, source/destination eid, sender, receiver, guid, and message fields.
Open tool - web3
LayerZero DVN Config Decoder
Decode a LayerZero V2 ULN (DVN) config — the raw bytes from getConfig(), or a full setConfig(...) calldata — into human-readable Confirmations, Required/Optional DVN lists resolved to provider names, and Optional DVN Threshold.
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