Free Online Developer Tools
— 200+ tools, zero signup
JSON formatter, Base64, text utilities, SEO tools, converters and calculators — all free, all in your browser, no tracking.
const data = JSON.parse(input);
{
"name": "Nex-WebTools",
"tools": 200,
"free": true,
"tracking": false,
"categories": [
"JSON", "Text",
"Code", "Security"
]
}
JSON / Data Tools 15 tools
Format, validate, and convert JSON, CSV, YAML, and XML — all in your browser.
JSON Formatter
Prettify minified JSON with customizable indentation.
→JSON Minifier
Compress JSON by stripping all unnecessary whitespace.
→JSON Validator
Check validity with detailed error pinpointing.
→JSON → CSV
Convert JSON arrays into downloadable CSV files.
→CSV → JSON
Parse CSV data into structured JSON arrays.
→JSON → YAML
Convert JSON into human-readable YAML.
→YAML → JSON
Parse YAML back into formatted JSON.
→JSON → XML
Convert JSON into well-formed XML documents.
→CSV Sorter
Sort CSV data by any column, ascending or descending.
→CSV Filter
Filter CSV rows by column conditions.
→CSV Column Extractor
Extract specific columns from CSV data.
→CSV Duplicate Finder
Find and highlight duplicate rows in CSV.
→CSV Statistics
Get min, max, mean, median & more per column.
→CSV Difference Checker
Compare two CSV files side by side.
→Large CSV Splitter
Split large CSV files into smaller chunks.
→Encoding / Decoding 7 tools
Encode, decode, escape, and inspect data — Base64, URLs, HTML entities, JWTs, and Unicode.
Base64 Encode/Decode
Convert text and files to and from Base64.
→URL Encode/Decode
Percent-encode special characters for safe URLs.
→HTML Entities
Encode & decode HTML special characters.
→JWT Decoder
Decode JSON Web Tokens — inspect header & payload.
→Unicode Escape
Escape and unescape Unicode \\u sequences.
→AES Encrypt / Decrypt
AES-256 text encryption with password.
→Random Token Generator
Generate secure random hex, base64 & UUID tokens.
→Text Tools 12 tools
Count, convert, compare, sort, and transform text — all in your browser.
Word & Char Counter
Count words, characters, sentences, paragraphs & reading time.
→Lorem Ipsum Generator
Generate placeholder paragraphs, sentences, or words.
→Text Case Converter
UPPER, lower, Title, camelCase, snake_case, kebab-case.
→Text Diff / Compare
Side-by-side comparison with colored diff output.
→Duplicate Line Remover
Remove repeated lines, keep unique entries.
→Text Sort (A-Z)
Sort lines alphabetically, numerically, or by length.
→Find & Replace
Search and replace with regex support.
→Markdown → HTML
Convert Markdown to clean HTML with live preview.
→HTML → Markdown
Convert HTML markup back to readable Markdown.
→Password Entropy Checker
Analyze password strength, entropy & crack time.
→Secure Notes
Encrypted local note-taking in your browser.
→Study Planner
Plan study sessions with topics & time allocation.
→Code / Developer Tools 20 tools
Format code, test regex, pick colors, generate CSS, convert timestamps, and more.
HTML Formatter
Beautify & indent messy HTML code.
→CSS Formatter/Minifier
Format or compress CSS stylesheets.
→JS Formatter/Minifier
Beautify or minify JavaScript code.
→SQL Formatter
Prettify SQL queries with keyword formatting.
→Regex Tester
Test patterns with match highlighting & cheat sheet.
→Color Picker
HEX ↔ RGB ↔ HSL converter with visual picker.
→CSS Gradient Generator
Build gradients visually with copy-paste CSS.
→Box Shadow Generator
Build CSS box-shadows with live preview.
→Unix Timestamp
Epoch ↔ human-readable date converter.
→Cron Expression Parser
Explain cron schedules in plain English.
→HTML Table Generator
Visual rows/cols builder → HTML code.
→Flexbox Playground
Visual CSS Flexbox layout builder.
→CSS Grid Generator
Visual CSS Grid layout builder.
→Viewport Tester
Test responsive breakpoints for any URL.
→Folder Tree Generator
Generate ASCII folder tree structures.
→Commit Message Generator
Build conventional commit messages.
→Code Line Counter
Count code, comment & blank lines.
→Syntax Diff
Side-by-side code diff with line & word-level highlighting.
→SQL Corrector
Fix SQL errors for any database & IDE.
→XML Viewer & Editor
Format, minify, validate XML with tree view & XPath.
→Hash / Crypto Tools 5 tools
Generate hashes, UUIDs, and secure passwords — all using browser crypto APIs.
Hash Generator
MD5, SHA-1, SHA-256, SHA-512 via Web Crypto API.
→UUID Generator
Cryptographically random v4 UUIDs.
→Password Generator
Secure passwords with custom length & symbols.
→Bcrypt Hash
Generate & verify bcrypt password hashes.
→File Hash Verifier
Calculate & verify file hashes (MD5, SHA-1, SHA-256).
→Image Tools 12 tools
Resize, convert, compress, and encode images — all using the Canvas API, no server needed.
Image Resizer
Resize images to exact pixel dimensions in browser.
→Image to Base64
Convert images to Base64 data URIs.
→Image Format Converter
Convert between PNG, JPG, WEBP, BMP, AVIF, GIF & ICO.
→Image Compressor
Reduce image file size with quality control.
→Image Cropper
Crop images visually in your browser.
→Batch Image Resize
Resize multiple images at once.
→EXIF Viewer
View image EXIF metadata details.
→EXIF Remover
Strip EXIF metadata from images.
→Dominant Color Extractor
Extract dominant colors from any image.
→Image Blur Tool
Apply blur effects to images.
→Pixelate Tool
Pixelate images or specific regions.
→DPI Changer
Change image DPI for print or web.
→Generators & Utilities 4 tools
QR codes, placeholder images, legal page generators, byte converter, and other essential web utilities.
Unit Converters 15 tools
Convert length, weight, temperature, speed, area, volume, and more — instant, accurate results.
Length Converter
Convert meters, feet, inches, km, miles & more.
→Weight / Mass Converter
Convert kg, lbs, ounces, grams & stones.
→Temperature Converter
Convert Celsius, Fahrenheit & Kelvin.
→Speed Converter
Convert km/h, mph, knots & m/s.
→Area Converter
Convert sq ft, sq m, acres & hectares.
→Volume Converter
Convert liters, gallons, cups, ml & fl oz.
→Time Converter
Convert seconds, minutes, hours, days & weeks.
→Pressure Converter
Convert PSI, bar, atm, Pa & mmHg.
→Energy Converter
Convert joules, calories, kWh & BTU.
→Power Converter
Convert watts, horsepower, kW & BTU/h.
→Fuel Economy Converter
Convert mpg, km/L & L/100km.
→Data Storage Converter
Convert bytes, KB, MB, GB, TB & PB.
→Frequency Converter
Convert Hz, kHz, MHz & GHz.
→Angle Converter
Convert degrees, radians & gradians.
→Force Converter
Convert newtons, lbf, dynes & kgf.
→Number System Converters 6 tools
Convert between decimal, binary, hexadecimal, octal, Roman numerals, and any base 2–36.
Decimal ↔ Binary
Convert decimal to binary & back instantly.
→Decimal ↔ Hexadecimal
Convert decimal to hex & back instantly.
→Decimal ↔ Octal
Convert decimal to octal & back instantly.
→Binary ↔ Hex
Convert binary to hexadecimal & back.
→Roman ↔ Decimal
Roman numerals to numbers & back.
→Number Base Converter
Convert between any base from 2 to 36.
→Color Converters 6 tools
Convert between HEX, RGB, HSL, CMYK, named colors, and Tailwind CSS color classes.
HEX ↔ RGB
Convert HEX color codes to RGB values & back.
→RGB ↔ HSL
Convert RGB to HSL color values & back.
→HEX ↔ HSL
Convert HEX to HSL color values & back.
→RGB ↔ CMYK
Convert RGB to CMYK for print design.
→Color Name ↔ HEX
Look up named CSS colors & their HEX values.
→Tailwind ↔ HEX/RGB
Tailwind CSS color class lookup tool.
→Text / String Converters 10 tools
Convert text to binary, hex, ASCII, Morse code, and transform between data formats like JSON, CSV, Markdown, SQL, TypeScript, Go, and TOML.
Text ↔ Binary
Convert text to binary representation & back.
→Text ↔ Hex
Convert text to hexadecimal & back.
→Text ↔ ASCII
Convert text to ASCII codes & back.
→Text ↔ Morse Code
Encode & decode Morse code.
→Markdown ↔ Plain Text
Strip or preview Markdown formatting.
→CSV ↔ Markdown Table
Convert CSV to Markdown table & back.
→JSON ↔ TypeScript
Generate TypeScript interfaces from JSON.
→JSON ↔ SQL CREATE
Generate SQL CREATE TABLE from JSON.
→JSON ↔ Go Struct
Generate Go structs from JSON data.
→TOML ↔ JSON
Convert between TOML and JSON.
→Date & Time Converters 5 tools
Unix timestamps, time zones, date formats, age calculation, and date difference tools.
Unix Timestamp ↔ Date
Convert Unix epoch to human-readable dates & back.
→Time Zone Converter
Convert times across world time zones.
→Date Format Converter
Convert between ISO, US, EU & custom formats.
→Age Calculator
Calculate exact age from date of birth.
→Days Between Dates
Count days, weeks & months between dates.
→Media / File Converters 4 tools
Convert SVG to PNG, pixels to REM/EM, images to data URIs, and Markdown to HTML.
Finance / Math Converters 7 tools
Fraction/decimal/percentage, scientific notation, and loan EMI calculator.
Fraction ↔ Decimal ↔ %
Convert between fractions, decimals & percentages.
→Scientific Notation
Convert scientific ↔ standard notation.
→Loan / EMI Calculator
Calculate monthly EMI & loan breakdown.
→Matrix Calculator
Add, multiply & transpose matrices.
→Quadratic Solver
Solve ax² + bx + c = 0 equations.
→Statistics Calculator
Mean, median, mode, std dev & more.
→HCF / LCM Calculator
Find HCF & LCM of any numbers.
→Personal Finance Calculators 12 tools
SIP, lumpsum, FD, RD, CAGR, EMI reverse, salary, GST, inflation, retirement, currency & mortgage calculator.
SIP Calculator
Calculate SIP mutual fund returns with compounding.
→Lumpsum Calculator
One-time investment growth with compound interest.
→FD Calculator
Fixed Deposit maturity amount & interest earned.
→RD Calculator
Recurring Deposit returns on monthly contributions.
→CAGR Calculator
Compound annual growth rate of investments.
→EMI Reverse Calculator
Find max loan amount from your EMI budget.
→Salary In-Hand Calculator
CTC to monthly take-home salary (India).
→GST Calculator
Add/remove GST with CGST/SGST/IGST split.
→Inflation Calculator
Future cost & purchasing power erosion.
→Retirement Planner
Plan retirement corpus & monthly SIP needed.
→Currency Converter
Convert 150+ currencies with live exchange rates.
→Mortgage Calculator
Home loan payments with taxes, PMI & amortization.
→Student Tools 6 tools
Attendance tracker, grade converter, flashcards, quiz builder, graph plotter & formula sheets.
Attendance Calculator
Track attendance % & classes to skip or attend.
→Marks → Grade Converter
Convert marks to grades (CBSE, VTU, US, UK).
→Flashcard Generator
Create & study flashcards with flip animation.
→Quiz Builder
Build & take MCQ quizzes with instant scoring.
→Graph Plotter
Plot math functions like sin(x), x² on a graph.
→Formula Sheet Generator
Build & print organized formula reference sheets.
→UI / CSS Generators 3 tools
Neumorphism, glassmorphism & theme palette generators with live preview and copyable CSS.
Security / Privacy Tools 3 tools
AES encryption, secure notes & random token generation — all client-side.
Dev Productivity 3 tools
Folder tree generator, conventional commits & code line counter for developers.
Health & Fitness 10 tools
BMI, TDEE, body fat, water intake, heart rate zones, pregnancy, sleep, macros, BP & age calculators.
BMI Calculator
Body Mass Index with visual category scale.
→TDEE & Calorie Calculator
Daily calories for maintain, lose & gain.
→Body Fat % Calculator
Estimate body fat using US Navy method.
→Water Intake Calculator
Daily water recommendation by weight & activity.
→Heart Rate Zone Calculator
Fat-burn, cardio & peak training zones.
→Pregnancy Due Date Calculator
Due date & trimester timeline from LMP.
→Sleep Cycle Calculator
Optimal sleep & wake times by 90-min cycles.
→Macro Calculator
Daily protein, carbs & fat breakdown.
→Blood Pressure Checker
BP category & risk level assessment.
→Age Calculator
Exact age, birthday countdown & fun stats.
→SEO Tools 40 tools
Comprehensive SEO toolkit: on-page analysis, technical SEO, keyword research, structured data, social previews, link analysis, local SEO, performance & audit tools.
Meta Tag Generator
Open Graph, Twitter Card & SEO meta tags.
→Meta Tag Analyzer
Extract & audit all SEO meta tags from HTML.
→SERP Preview Tool
Preview how your page looks in Google search.
→Heading Structure Checker
Visualize H1-H6 hierarchy & find issues.
→SEO Score Calculator
On-page SEO scoring with actionable checklist.
→Article SEO Scorer
Score article content for keyword & readability.
→Image SEO Checker
Audit images for alt text, filenames & formats.
→SEO Title A/B Tester
Compare title tags side-by-side for CTR potential.
→robots.txt Generator
Create robots.txt for search crawlers.
→Robots.txt Tester
Test URL allow/block rules in robots.txt.
→Sitemap XML Generator
Create XML sitemaps for search engines.
→Sitemap XML Validator
Validate sitemap structure, URLs & duplicates.
→.htaccess Redirects
Apache 301/302 redirect rules generator.
→Slug Generator
Convert titles to SEO-friendly URL slugs.
→Hreflang Tag Generator
Multilingual SEO hreflang link tags.
→Canonical URL Checker
Find & validate canonical tags in HTML.
→Redirect Chain Simulator
Trace redirect paths, find loops & chain issues.
→Sitemap Index Generator
Generate sitemapindex XML for large sites.
→Meta Robots Tag Generator
Build noindex, nofollow & other directives.
→Keyword Density Checker
Analyze word frequency & keyword density.
→Keyword Suggestion Tool
Generate long-tail keyword ideas from a seed.
→Bulk Keyword Combiner
Generate all keyword combinations from lists.
→Readability Scorer
Flesch-Kincaid, Gunning Fog & more indices.
→Keyword Intent Classifier
Classify keywords by search intent type.
→SEO Word Counter
Word count, reading time & keyword density.
→Schema Markup Generator
JSON-LD structured data for rich results.
→FAQ Schema Generator
FAQ structured data for Google rich results.
→Breadcrumb Schema Generator
BreadcrumbList JSON-LD for navigation rich results.
→Structured Data Validator
Validate JSON-LD for syntax & required fields.
→Rich Snippet Preview
Preview Google rich result cards for any schema type.
→Open Graph Preview
Preview social sharing on FB, LinkedIn, Twitter & Discord.
→Twitter Card Generator
Generate Twitter card meta tags with live preview.
→UTM Link Builder
Build campaign tracking URLs with UTM params.
→Internal Link Analyzer
Extract, classify & audit all page links.
→Domain Authority Estimator
Estimate DA score from backlinks & site metrics.
→Anchor Text Planner
Plan natural backlink anchor distribution.
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