Online Tools & Utilities
Free, fast, and easy-to-use web tools for everyone. Streamline your workflow with our comprehensive suite of 172+ utilities.
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Building a Production CLI Tool with Node.js
Ship a production-ready CLI in days, not weeks.
Master the art of building professional command-line tools. From scaffolding to publishing—learn best practices, testing, and deployment strategies used in production.
- Production-ready patterns
- Testing, CI, and npm publish
- Real-world examples
Find the Perfect Tool
Search through our collection of tools or browse by category to find exactly what you need
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SaaS tools and books we build alongside Rapid Tools Online — same quality bar, built for real workflows.
SuperApps
Build custom internal apps with tables, calendar, gallery, and more—no code required. Streamline ops and data in one place.
Explore SuperAppsWateronix
Water delivery management for large RO plants in Pakistan: routes, billing, drivers, and reporting—built for serious operations, not chat threads.
See WateronixProduction CLI with Node.js (PDF)
Also in our catalog: ship a production-ready command-line tool—from scaffolding to tests and publish. Same guide promoted site-wide; grab it here too.
View on GumroadPopular Tools
Most used converters and utilities — free, instant, no sign-up
✨ New Tools
12 new toolsCoordinate Converter
Convert between coordinate systems including decimal degrees, DMS, UTM, and MGRS. Essential for GPS navigation, surveying, mapping, and military applications.
YAML Formatter and Validator
Format and validate YAML with consistent indentation. No conversion to JSON.
XML Schema (XSD) Validator
Check that your XML document and XSD schema are well-formed. Paste both and validate syntax.
Unit Price Calculator
Calculate price per unit from total price and quantity. Compare two products to see which is cheaper per oz, kg, or any unit.
TOML Formatter and Validator
Format and validate TOML. Re-serialize with consistent structure. No conversion to JSON.
Text and Word Frequency Counter
Count character or word frequency in text. Sort by count or name. Ignore case, spaces, or punctuation.
SSL Certificate Checker
Check SSL/TLS certificate validity, issuer, subject, and SANs. Paste PEM or upload .pem/.crt. Client-side only.
XML JSON Converter
Convert XML to JSON and JSON to XML with validation and formatting controls. Client-side conversion for API payloads and integration workflows.
JWT JWKS Inspector
Decode JWT, inspect claims, and verify RS256-family signatures against JWKS keys using kid matching. Client-side only.
HMAC Signature Generator
Generate and compare HMAC signatures for webhook and API request debugging. Supports SHA-256, SHA-384, and SHA-512 with hex or base64 output.
Webhook Signature Verifier
Verify webhook signatures for GitHub, Stripe, Slack, and generic HMAC payloads. Compare expected and received signatures instantly.
Sprint Capacity Calculator
Compare team capacity and committed story points. Sprint length, team size, capacity %, optional velocity.
Recently Updated
12 updatedHash Generator
Generate MD5, SHA1, SHA256, and SHA512 from text or file upload. File hash, checksum from file, verify file integrity. Client-side only.
Calendar
Manage and view events by day, week, or month in a smart calendar interface
Budget Planner
Take control of your finances with comprehensive budget planning. Track income, expenses, set budgets, and achieve financial goals with detailed analytics
Invoice Generator
Create professional invoices with client details, line items, taxes, discounts, and totals. Perfect for freelancers and small businesses
Quote & Estimate Builder
Build clear quotes and estimates with itemized services, optional add-ons, and built-in totals for faster approvals
Expense Tracker
Track daily business expenses by category, add notes, and export summaries for bookkeeping and tax prep
Appointment Scheduler
Create simple appointment schedules, available time slots, and customer bookings
Percentage Calculator
Calculate percentages, percentage increase/decrease, find percentage of a number, and solve percentage problems with step-by-step solutions
Average Calculator
Calculate mean, median, mode, range, standard deviation, and variance with step-by-step calculations and data visualization
Percent Error Calculator
Calculate percent error between experimental and theoretical values
Weighted Average Calculator
Calculate weighted averages where different values have different importance or weights
UUID Generator
Generate RFC 4122 compliant UUIDs (v1 and v4) with multiple output formats for databases, APIs, and applications
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