Free Online Tools for Developers and IT Administrators
Check DNS propagation, generate passwords, create UUIDs, calculate hashes, encode/decode Base64/URL, or analyze SAML responses in one place for web development and security operations.
Tools
26Categories
4Related guides
6
Tool catalog
Tool catalog
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Random Password and Random String Generator
Generate secure random passwords and random strings with letters, numbers, and symbols in one click.
Passphrase Generator
Generate long, memorable passphrases in the browser by combining multiple random words.
Japanese Sentence Passphrase Generator (Romaji)
Generate passphrases based on short Japanese-like sentences and output them in romaji.
UUID Generator
Create unique v4 UUIDs instantly.
Advanced Hash Generator Tool
Generate hashes with SHA-256 / SHA-384 / SHA-512 / SHA-512/256, SHA3-256 / SHA3-512, BLAKE2b-256 / BLAKE2b-512, Keccak, and legacy compatibility algorithms such as MD5, SHA-1, and RIPEMD160. Supports HMAC, Base64 output, file input, copy, and download.
SAML Request/Response Analysis Tool
A free tool that Base64 decodes SAML requests and responses and displays them as formatted XML.
SAML Decryptor
Free tool to decrypt encrypted SAML Response / AuthnRequest / LogoutRequest messages with a PEM private key and show the decrypted XML and analysis result.
SAML Test (SP / IdP)
Public SAML test environment for SP / IdP integration checks, metadata registration, SSO testing, and attribute inspection.
SSL/TLS Checker
Enter a domain to inspect expiry, SAN, issuer, chain, OCSP/CRL, and cipher/protocol in one shot. Lightweight summary first, detailed cards on demand.
CSR Generator & Linter
Create RSA/ECDSA keys and CSRs with CN/SAN, or paste an existing CSR to extract SAN, KeyUsage, and signature algorithm.
Certificate Decoder
Paste or upload PEM/DER/PKCS#7/PKCS#12 and extract expiry, SAN, KeyUsage/ExtKeyUsage, fingerprints, OCSP/CRL URLs.
Key & Certificate Matcher
Verify that a server certificate matches its private key and highlight missing or misordered intermediates.
Signature Algorithm & Strength Assessor
Analyze certificates or CSRs, score RSA key length / ECDSA curve / signature hash strength, and suggest improvements.
OCSP / CRL Status Checker
Call OCSP in real time using the certificate and issuer to see revocation status, responder, and This/Next Update. CRL URLs are also shown.
QR Code Generator
Convert text or URLs into QR codes with SVG/PNG/JPEG download, 24-hour shareable links, Data URL copy, and customization for size, margin, colors, and error correction (L/M/Q/H).
Encode/Decode tool
Conversion tool that supports Base64, URL, HTML encoding, etc.
JSON Formatter / Validator
Browser-based JSON formatter, minifier, and validator. Invalid JSON shows an approximate error line and column.
XML Formatter / Validator
Browser-based XML formatter, minifier, and validator. Invalid XML shows a parse error with approximate line and column hints, and formatted output can be copied directly.
JSON to CSV Converter
Browser-based JSON to CSV converter with direct download. Arrays of objects become rows, and nested keys are flattened with dot notation.
Unit Converter
Convert data size, volume, length, weight, temperature, area, speed, and time in one place. Supports KB/MB/GB, L/mL, km, kg, °C/°F, and more.
Client Insight
Inspect browser details, IP, and location directly in the browser. Nothing is stored; everything stays on this page.
Unix Time Converter Tool
Convert between Unix timestamps and date/time with timezone offsets and history support.
Subnet Mask Calculator
Calculate IPv4 network, broadcast, wildcard masks, and usable host ranges from IP and CIDR.
What Is My IP?
Show the IP address currently visible to this site right away. Includes IPv4/IPv6 detection, HTTPS status, and proxy-related headers.
DNS Lookup & Propagation Checker
Query A/AAAA/CNAME/MX/TXT/CAA records across Google, Cloudflare, Quad9, and OpenDNS to compare propagation and answer differences.
Mail DNS Authentication Checker
Check SPF, DMARC, and DKIM public keys for a domain in one place. Review published records, policy mode, key size, and common setup issues.
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Task routes
Inspect certificate health
Start with expiry and status, then dig into OCSP and certificate details.
Prepare secrets and identifiers
Generate passwords, memorable phrases, hashes, and IDs in one flow.
Inspect SAML requests and responses
Jump into request and response analysis, including encrypted response decryption when needed.
Clean up text and payloads
Format JSON, convert to CSV, encode content, or publish a QR output.
Run network triage
Check DNS, IP visibility, email auth, and subnet information from one route.
Related guides
Subnet mask basics
Review CIDR notation, network addresses, and broadcast logic.
CIDR reference /16 to /32
See masks, total addresses, and usable hosts in one table.
Subnet splitting examples
Follow /24 to /25 /26 examples and a larger /18 to /24 split.
SAML SP test basics
Review EntityID, ACS, AuthnRequest, and attribute checks for SP-side testing.
SAML IdP test basics
Review SSO, SLO, fixed users, and the SP-side checks that matter most.
SAML metadata checklist
Check EntityID, ACS / SSO / SLO endpoints, certificates, and NameID assumptions before testing.
Contact
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