PrepApp web tools
Find the right tool faster
Browse free tools for JSON, APIs, security, data cleanup, DevOps, and AI workflows.
Tools
60
Categories
17
JSON Formatter
Format, beautify, and validate JSON online with a fast free developer tool.
JWT Decoder
Decode JSON Web Tokens online and inspect their header and payload in your browser.
JWT Secret Key Generator
Generate a strong random JWT secret key online for development and testing.
Base64 Encoder
Encode text to Base64 online quickly and securely in your browser.
URL Encoder
Encode URLs and query parameters online for safe use in web applications.
UUID Generator
Generate random UUIDs online for applications, APIs, databases, and testing.
DNS Lookup
Look up A, AAAA, MX, NS, TXT, CNAME, and other DNS records for any domain.
HTTP Headers Checker
Inspect HTTP response headers, status codes, and web security settings for a website.
IP Lookup
Find location, ISP, and technical details for an IPv4 or IPv6 address.
SSL Certificate Checker
Check SSL certificate validity, expiry, issuer, and domain coverage for a website.
Subdomain Checker
Discover and validate subdomains for a domain with a fast reconnaissance-style check.
WHOIS Lookup
Search domain registration details and ownership metadata for a website or domain.
CSV Data Cleaner
Clean, normalize, and transform CSV files directly in the browser.
Data Profiling
Profile uploaded CSV data to understand column types, completeness, and quality.
Data Quality Checker
Review CSV data for missing values, duplicates, invalid formats, and inconsistent columns.
SQL Query Analyzer & Generator
Analyze SQL syntax and structure while generating readable, reviewable SQL statements.
REST API Tester
Test REST APIs online with a free REST API testing and debugging tool. Send GET, POST, PUT, PATCH and DELETE requests and inspect API responses instantly.
Dockerfile Generator
Create a Dockerfile online for common web development languages and frameworks.
Robots.txt Validator
Validate robots.txt rules online and check whether crawlers can access your URLs.
JSON to Code Converter
Convert JSON data into typed or language-specific code for 13 popular programming languages.
Web Vulnerability Scanner
Review browser-accessible HTTPS, security headers, and basic server information for a website.
Icon Size Converter
Convert a 512×512 image into multiple common PNG icon sizes directly in your browser.
Meta Tag Generator
Generate standard HTML meta tags for SEO, social sharing, and browser metadata in seconds.
Open Graph Generator
Generate Open Graph meta tags for better social previews and share cards on Facebook, LinkedIn, and more.
Redirect Checker
Analyze URL redirects and see the chain of HTTP status codes and location changes for a page.
Schema Markup Generator
Create structured JSON-LD schema markup for articles, products, organizations, FAQs, and more.
Sitemap Generator
Generate a sitemap.xml file with URLs, last modified values, change frequency, and priorities.
Error Message Parser
Parse application errors and logs into structured details, including type, category, and severity.
Log Formatter
Format raw application logs into a clean, numbered, readable layout.
Log Level Filter
Filter application and server logs to show only selected log levels.
Apache & Nginx Log Parser
Parse Apache and Nginx access logs into structured request data.
Log Timestamp Converter
Convert common log timestamps and Unix timestamps into readable date formats.
Log to JSON Converter
Convert timestamped application log lines into structured JSON records.
Stack Trace Formatter
Format JavaScript, Java, and Python stack traces into a structured summary.
Structured Logging Generator
Generate structured JSON log entries with service, environment, and request metadata.
Gitignore Generator
Generate a .gitignore file with rules for popular languages, frameworks, and tools.
CI/CD Pipeline Generator
Generate a CI/CD workflow for popular platforms, languages, and deployment targets.
Cron Expression Generator
Build and interpret cron expressions for recurring scheduled tasks.
Docker Command Generator
Assemble common Docker commands for containers, images, networks, and volumes.
Kubernetes Deployment Generator
Configure and generate a Kubernetes Deployment manifest for an application.
Kubernetes YAML Generator
Generate common Kubernetes resource manifests, including Deployments, Services, and ConfigMaps.
Linux Command Generator
Construct common Linux commands for file management, processes, networking, and system tasks.
Linux Permission Calculator
Calculate Linux file permissions and their numeric chmod representation.
Nginx Config Generator
Create a starting Nginx configuration for common web server and reverse proxy setups.
SSH Command Generator
Build SSH commands for remote connections, file transfers, and port forwarding.
AI Prompt Generator
Create clear and structured prompts for AI models.
AI JSON Prompt Generator
Generate structured AI prompts in clean JSON format.
AI Prompt Optimizer
Improve AI prompts with clearer instructions, structure, and output requirements.
AI Text Summarizer
Summarize articles, notes, documentation, and other text directly in your browser.
AI Token Counter
Prepare and inspect AI prompt text before using it with a language model.
LLM Cost Calculator
Estimate AI API costs from input and output token usage.
System Prompt Generator
Create structured system instructions for AI applications.
Notion Notes Prompt Generator
Turn a course outline, lecture, topic, or rough notes into a structured prompt for Notion-ready study notes.
ResumeForge
Create and refine a professional resume with ATS-friendly sections, a live preview, and export-ready LaTeX output.
Portfolio Builder
Create a personal portfolio website without coding. Add your profile, skills, projects, education, and experience, preview the design, then download a ready-to-publish website as a ZIP file.
Career Roadmap Tool
Plan your education and career path after Class 10 or 12 with stream, course, and job route guidance.
Developer Roadmaps
Explore guided learning roadmaps for full-stack, AI, data, and career-focused development paths.
Academic Countdown
Track exam deadlines, assignments, interviews, and other academic milestones with a live countdown dashboard.
Productivity Clock
Focus with a Pomodoro-style timer, task tracker, and daily session summary for college and work routines.
University Exam Guide
Practical university exam advice on PYQs, revision, answer writing, and time management to help you prepare with confidence.