Everyday tools for developers and network engineers.
Format JSON, plan subnets, decode tokens, convert timestamps and more. Each tool says where your input goes.
Data and text
- JSON formatterFormat, validate, query and repair JSON.
- Regex testerTest a regular expression against sample text.
- Text diffLine and word differences between two texts.
- Case convertercamelCase, snake_case, kebab-case and other cases.
- YAML to JSONConvert YAML to JSON and JSON to YAML.
- JSON to TypeScriptTypeScript interfaces from a JSON sample.
- Lorem ipsum generatorPlaceholder text in paragraphs, sentences or words.
- CSV to JSONConvert CSV to JSON and JSON to CSV.
- SQL formatterFormat SQL queries for PostgreSQL, MySQL and more.
- XML formatterFormat, minify and check XML.
- Markdown editorWrite Markdown with a live preview, then copy the HTML.
Network
- Subnet calculatorNetwork, broadcast, host range and mask for a block.
- VLSM calculatorSubnets sized from host counts, no overlaps.
- What's my IPUses our serverYour public IP address, as our server sees it.
- DNS lookupSent to a DNS resolverA, AAAA, MX, TXT and other records for a domain.
- IP range to CIDRThe fewest CIDR blocks for an IP range, and back.
- MAC address lookupUses our serverThe vendor behind a MAC address, from the IEEE registry.
Encoding
- Base64 encoderEncode and decode Base64 and Base64url, text or files.
- URL encoderPercent-encode and decode URLs and query strings.
- HTML entity encoderEscape and unescape HTML entities like & and <.
- QR code generatorQR codes for links, Wi-Fi, contacts and more.
- JWT decoderDecode a JSON Web Token and verify its signature.
- Certificate decoderDecode an SSL certificate, chain or CSR.
- Number base converterHex, decimal, binary and octal, any size.
- Colour converterHEX, RGB, HSL and OKLCH, with a contrast check.
Hashes and IDs
Time
System
No tools match.
Where your input goes
Each tool says what leaves your browser.
29 of the 32 tools listed above process your input in this browser tab; no request carries it.
- What's my IP uses our server (your IP address, which every request carries); its row is marked.
- The DNS lookup sends the domain name to the public DNS resolver you choose (Cloudflare or Quad9); its row is marked.
- MAC address lookup uses our server (the vendor prefix only: the first 6 hex digits of the MAC address); its row is marked.
You can check it in DevTools, and each tool's page says the same next to the tool. Every tool, one by one.