Free Web Utilities

Developer Tools Directory

Free developer utilities to decode signatures, check network status records, verify SSL configurations, and debug payloads.

Security & Auth

JWT Decoder

Decode and inspect JSON Web Token headers, payload claims, and check expiration values locally.

Open Tool
Security & Auth

SSL Inspector

Verify SSL/TLS certificate chains, issuer details, security parameters, and expiration limits.

Open Tool
Converters

JSON Formatter

Prettify, format, validate, and minify raw JSON string payloads locally in your browser.

Open Tool
Converters

UUID / ULID Generator

Bulk generate cryptographically secure UUID v4 and lexicographically sortable ULID strings.

Open Tool
Diagnostics

Regex Tester

Test, match, validate, and debug JavaScript regular expressions with real-time group highlights.

Open Tool
Diagnostics

Cron Translator

Translate, humanize, and check simulated execution schedules for standard cron expression patterns.

Open Tool
Network & DNS

DNS Lookup Utility

Query dynamic A, AAAA, MX, TXT, and CNAME records for any domain from root servers.

Open Tool
Network & DNS

SPF Record Generator

Build and validate DNS Sender Policy Framework (SPF) rules to authenticate secure email delivery.

Open Tool
Network & DNS

CIDR Subnet Calculator

Calculate IP subnet address allocations, wildcard masks, host ranges, and join paths.

Open Tool
Diagnostics

Website Uptime Checker

Check if any server endpoint is responding online from global network validation points.

Open Tool
Diagnostics

HTTP Header Checker

Analyze HTTP request/response headers, security policy overrides, and server directives.

Open Tool
Diagnostics

HTTP Status Checker

Verify server redirection loops, destination endpoints, and status code outputs.

Open Tool
Converters

Base64 Encoder & Decoder

Encode plain text or file parameters to base64 format and decode them back instantly.

Open Tool
Converters

Cron Expression Builder

Create and translate standard cron scheduler strings with an interactive calendar preview.

Open Tool
Converters

Robots.txt Generator

Produce crawling directives for Googlebot and other crawler agents to guide search indexers.

Open Tool
Converters

SLA Downtime Calculator

Map target service availability percentages to equivalent daily, weekly, or yearly down limits.

Open Tool
Diagnostics

Webhook Tester

Register temporary HTTP callback targets to capture and inspect incoming webhook JSON payloads.

Open Tool