LOCAL / BROWSER
Network & DNSIPv4 Subnet Planner
Divide an IPv4 network into named allocations and join sibling blocks without losing sight of the address space.
The directory / 16 tools
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16 of 16 tools / nothing to install
LIVE / API
Network & DNSDNS Explorer
Inspect public DNS records with clear distinctions between answers, missing records and resolver failures.
LIVE / API
Network & DNSEmail DNS Policy
Inspect published SPF, DMARC and a supplied DKIM selector, with the limits of DNS-only analysis made explicit.
LIVE / API
Network & DNSHTTP Inspector
Follow a bounded public redirect chain and examine status codes and response headers without loading the page.
LOCAL / BROWSER
Network & DNSEmail Header Analyzer
Unfold message headers and inspect routing and reported authentication locally, without claiming to verify the sender.
LOCAL / BROWSER
Security & identityChmod Calculator
Translate Unix permission bits, octal modes and symbolic changes, including setuid, setgid and sticky bits.
LOCAL / BROWSER
Security & identityPassword & Passphrase Generator
Generate secrets with browser cryptographic randomness and clearly stated character or word selection rules.
LOCAL / BROWSER
Development & dataJSON & YAML Workbench
Validate, format and convert structured text while protecting large numeric values from silent rounding.
LOCAL / BROWSER
Text & encodingBase64 Encoder & Decoder
Encode UTF-8 text or hexadecimal bytes and decode standard or URL-safe Base64 with explicit error reporting.
LOCAL / BROWSER
Development & dataURL Workbench
Inspect URL components and ordered query parameters or transform encoded text without visiting any address.
LOCAL / BROWSER
Security & identityJWT Decoder
Read a three-part token and its timestamp claims locally; decoded content always remains unverified.
LOCAL / BROWSER
Security & identitySHA Checksums
Calculate SHA-256, SHA-384 and SHA-512 for text or bounded local files, with progress and cancellation.
LOCAL / BROWSER
Development & dataRegex Tester
Explore JavaScript regular expressions in a terminable worker with bounded input, match counts and execution time.
LOCAL / BROWSER
Text & encodingText Diff
Compare text by line or word and export a unified difference without rendering input as HTML.
LOCAL / BROWSER
Time & schedulingCron Helper
Inspect five-field cron schedules and upcoming instants in an explicit timezone using the documented parser rules.
LOCAL / BROWSER
Time & schedulingEpoch Time Converter
Convert explicitly selected seconds or milliseconds to timestamp displays without guessing the unit or timezone.