🛠️Developer Tools Collection

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Access our comprehensive collection of free online tools. From JSON formatting to data validation, we've got everything you need for development and productivity.

64 tools available

📄Merge & Split PDFPDF ToolsCombine PDFs into one, split a document into separate files, or extract just the pages you name — reorderable, no watermark and nothing uploaded.🌐What Is My IPNetwork ToolsYour public IP address, approximate location and ISP — plus a full readout of everything your browser reveals to every site you visit.📝Lorem Ipsum GeneratorDeveloper ToolsPlaceholder text by paragraph, sentence, word or list item — as plain text, HTML or Markdown, with naturally varying sentence lengths.🖼Image Resizer & CompressorImage ToolsResize by exact pixels, percentage or social preset, then compress to the file size you need — JPG, WebP or PNG, no watermark, nothing uploaded.🎼Chord FinderMedia ToolsLook up any chord on piano and guitar with playable shapes, interval breakdowns and audio — or click the notes you played and get the chord name back.🎸Guitar TunerMedia ToolsTune guitar, bass, ukulele or violin through your microphone with cent-accurate pitch detection, automatic string recognition and alternate tunings.🥁Tap BPM CounterMedia ToolsTap along with any song to find its tempo instantly, with a steadiness score, tempo marking and a table of tempo-synced delay times.🎵Online MetronomeMedia ToolsA rock-steady metronome scheduled on the audio clock so it never drifts — 20–300 BPM, time signatures, subdivisions, accented downbeat, tap tempo and a wood-block voice.🔠ASCII Art GeneratorImage ToolsTurn any image into text art with adjustable width and character sets — copy or download it, all privately in your browser.🗃️SQL FormatterDeveloper ToolsBeautify messy SQL into clean, readable queries with uppercased keywords and clause breaks, or minify to a single line — string-safe and private.⏱️Unix Timestamp ConverterDeveloper ToolsConvert Unix epoch time to a human date in UTC and local time and back to seconds or milliseconds, with a live clock and relative time.🔡Base64 Encode / DecodeDeveloper ToolsConvert text, images and files to and from Base64 data URLs with a live image preview — Unicode-safe and fully private in your browser.🔑JWT DecoderDeveloper ToolsDecode a JSON Web Token's header and payload, read its claims with human-readable expiry, and verify HS256 signatures — all privately in your browser.✍️Signature GeneratorProductivity ToolsDraw your signature with a mouse or finger, or type it in a handwriting font, then download a transparent PNG to sign PDFs and documents.🌍Time Zone ConverterProductivity ToolsConvert any date and time across cities worldwide and plan meetings, with daylight saving applied automatically for the exact date.🎲RandomizerProductivity ToolsGenerate random numbers (with a no-repeats option), roll dice, flip coins, and pick or shuffle names fairly — powered by cryptographic randomness.🔗URL Encoder / DecoderDeveloper ToolsPercent-encode text for URLs, forms and APIs, or decode %XX back to readable text — with an automatic query-parameter breakdown.📄JSON FormatterDeveloper ToolsFormat, validate, and beautify JSON data with syntax highlighting, error detection, and comparison features.🕐Date & Time CalculatorDeveloper ToolsCalculate time differences, days between dates, business days, age calculator, and countdown timers. Perfect for project planning.🧮Unit Price CalculatorCalculator ToolsCalculate prices per unit, convert measurements, compare costs across currencies. Perfect for shopping, cooking, and business.🏦Loan & EMI CalculatorCalculator ToolsCalculate monthly loan and mortgage payments (EMI), total interest, and total cost. Works for home, car, student, and personal loans — instantly in your browser.🧮Percentage CalculatorCalculator ToolsFind a percent of a number, work out what percent one value is of another, and calculate percentage increase or decrease — instantly as you type.🎂Age CalculatorCalculator ToolsFind your exact age in years, months, and days from your date of birth, with total weeks/days/hours and a countdown to your next birthday.💵Tip CalculatorCalculator ToolsCalculate the tip and split a bill any number of ways. Quick presets, per-person totals, and instant results for any restaurant or service.🎓GPA CalculatorCalculator ToolsCalculate your weighted GPA on the 4.0 scale from your course grades and credit hours. Add unlimited courses and see total credits instantly.🔬Scientific CalculatorCalculator ToolsA full scientific calculator with trigonometry, logarithms, powers, roots, and constants — with a safe expression evaluator and DEG/RAD modes.🔤Regex TesterDeveloper ToolsTest and debug regular expressions live with flag toggles, match highlighting, capture-group inspection, and a replacement preview.🔀Diff CheckerDeveloper ToolsCompare two blocks of text or code and see a clear line-by-line diff with added and removed lines highlighted. Runs entirely in your browser.📝Markdown EditorDeveloper ToolsWrite Markdown with a live HTML preview, a formatting toolbar, and one-click copy or download. Perfect for READMEs and documentation.⏲️Cron Expression BuilderDeveloper ToolsBuild and decode cron schedules with presets and a plain-English explanation of exactly when each expression runs.🔄JSON ↔ CSV ↔ YAML ConverterDeveloper ToolsConvert data freely between JSON, CSV, and YAML in your browser. Nothing is uploaded — all conversion happens locally on your device.🔳QR Code GeneratorDeveloper ToolsCreate custom QR codes for links, Wi-Fi, text, email, phone, and SMS. Adjust size and colors, then download a high-resolution PNG — all in your browser.🖼️HEIC to JPG ConverterImage ToolsConvert iPhone HEIC/HEIF photos to JPG or PNG, in batches, with adjustable quality. Runs entirely in your browser — nothing is uploaded.🔍Image to Text (OCR)Image ToolsExtract editable text from screenshots, photos, scans, and documents with in-browser OCR in multiple languages. Your images never leave your device.✂️Background RemoverImage ToolsErase the background from any image with an in-browser AI model and get a transparent PNG. No watermark, no sign-up, and your photo is never uploaded.📄PDF to JPGPDF ToolsConvert each page of a PDF into a JPG or PNG image with adjustable resolution and quality. Rendered locally in your browser — nothing uploaded.🔐Hash & Random GeneratorDeveloper ToolsGenerate UUIDs, cryptographic hashes, random strings, passwords, API keys, JWT tokens, and encode/decode data formats.🌐Website Uptime CheckerDeveloper ToolsMonitor website availability, check response times, and track uptime statistics with real-time status monitoring.🔍File AnalyzerDeveloper ToolsComprehensive file analysis tool that extracts metadata, technical details, security information, and complete file properties.📊CSV & Excel ViewerDeveloper ToolsProfessional data visualization tool for CSV and Excel files. Upload, parse, preview, filter, and analyze spreadsheet data with advanced features.🗜️Code MinifierDeveloper ToolsMinify HTML, CSS, and JavaScript code for production. Remove whitespace, comments, and optimize code size for faster loading.✍️Text UtilityDeveloper ToolsAll-in-one text toolkit with case converter, live word/character/sentence counter, specific term counter, cleanup tools, find/replace, and file upload support.🗂️ZIP ManagerDeveloper ToolsCreate ZIP from uploaded files, add optional password protection, upload ZIP files to inspect content, and unlock password-protected archives.✅Code ValidatorDeveloper ToolsValidate JSON, XML, YAML, TOML, INI, JavaScript, TypeScript, Python, HTML, SQL, and regex with detailed diagnostics.🛡️Encryptor / DecryptorSecurity ToolsEncrypt and decrypt text or files using repeating-key byte transformation with custom keys, random 512-bit key suggestions, and local output downloads.🧪Mouse & Keyboard TesterDeveloper ToolsTest mouse and keyboard input in real time with click/scroll counters, per-key counts, reset controls, clipboard copy, and exportable reports.📶Internet Speed TestNetwork ToolsFree, no-signup internet speed test. Measure download, upload, ping, and jitter against Cloudflare's global edge network — directly in your browser.🎡Wheel SpinnerProductivity ToolsRandom name picker with an animated wheel — perfect for raffles, classroom games, team standups, giveaways, and tie-breaker decisions.🏠Mortgage CalculatorCalculator ToolsEstimate your full monthly mortgage payment — principal, interest, taxes, insurance, PMI and HOA — and see how extra payments cut years off the loan.📈Compound & Simple Interest CalculatorCalculator ToolsCalculate compound or simple interest on savings and investments with monthly contributions, and a year-by-year chart of contributions vs interest earned.💼Salary ConverterCalculator ToolsConvert between hourly, daily, weekly, monthly and annual pay, and estimate take-home after deductions.💳Debt Payoff CalculatorCalculator ToolsCompare the snowball and avalanche strategies with your real debts — payoff date, total interest and the exact order to attack.🧾Invoice GeneratorProductivity ToolsCreate a professional invoice with line items, tax and discounts, live preview and one-click PDF download — free and private.🏖️Retirement CalculatorCalculator ToolsProject your nest egg at retirement, the income it can sustain under the 4% rule, and how long it lasts against your target spending.📉Inflation CalculatorCalculator ToolsConvert any dollar amount between 1913 and today using historical US CPI — see what money was really worth.⏱️Timesheet CalculatorCalculator ToolsAdd clock-in/out times and breaks to get weekly hours, overtime and gross pay — overnight shifts handled.🎥Screen RecorderMedia ToolsRecord your screen, window or tab with optional mic narration and download instantly — no install, no upload, no watermark.📡Internet Connection MonitorNetwork ToolsContinuously monitor your internet connection with live latency tracking, an outage log, and an audible alarm the moment it drops. Standard tones or your own audio.🔊Text to Speech ReaderMedia ToolsPaste any text and listen with natural system voices — adjustable speed and pitch, private and free.💪Health & Fitness CalculatorHealth & FitnessBMI, calories (TDEE), body fat, ideal weight, macros, water intake and pregnancy due date — seven trusted health calculators in one, metric or imperial.⏱️Online Timer & StopwatchProductivity ToolsA precise countdown timer, a lap stopwatch and a Pomodoro focus timer with a built-in alarm — accurate in background tabs and free.💱Currency ConverterCalculator ToolsConvert between 30+ world currencies using daily European Central Bank exchange rates. Fast, private, and works offline after the first load.📏Unit ConverterCalculator ToolsConvert length, weight, temperature, volume, area, speed, time, data and cooking measurements. cm to inches, kg to lbs, °C to °F and cups to grams — instantly.🧾Sales Tax, Discount & Margin CalculatorCalculator ToolsAdd or remove sales tax and VAT/GST, calculate discounts and savings, and price products with the right profit margin and markup — free and private.

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PDF Tools

Merge & Split PDF

Combine PDFs into one, split a document into separate files, or extract just the pages you name — reorderable, no watermark and nothing uploaded.

merge pdfsplit pdfcombine pdfextract pagespdfdocument

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In-Depth Guides

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📄Merge & Split PDF Guide 🌐What Is My IP Guide 📝Lorem Ipsum Generator Guide 🖼Image Resizer & Compressor Guide 🎼Chord Finder Guide 🎸Guitar Tuner Guide 🥁Tap BPM Counter Guide 🎵Online Metronome Guide 🔠ASCII Art Generator Guide 🗃️SQL Formatter Guide ⏱️Unix Timestamp Converter Guide 🔡Base64 Encode / Decode Guide 🔑JWT Decoder Guide ✍️Signature Generator Guide 🌍Time Zone Converter Guide 🎲Randomizer Guide 🔗URL Encoder / Decoder Guide 📄JSON Formatter Guide 🕐Date & Time Calculator Guide 🧮Unit Price Calculator Guide 🏦Loan & EMI Calculator Guide 🧮Percentage Calculator Guide 🎂Age Calculator Guide 💵Tip Calculator Guide 🎓GPA Calculator Guide 🔬Scientific Calculator Guide 🔤Regex Tester Guide 🔀Diff Checker Guide 📝Markdown Editor Guide ⏲️Cron Expression Builder Guide 🔄JSON ↔ CSV ↔ YAML Converter Guide 🔳QR Code Generator Guide 🖼️HEIC to JPG Converter Guide 🔍Image to Text (OCR) Guide ✂️Background Remover Guide 📄PDF to JPG Guide 🔐Hash & Random Generator Guide 🌐Website Uptime Checker Guide 🔍File Analyzer Guide 📊CSV & Excel Viewer Guide 🗜️Code Minifier Guide ✍️Text Utility Guide 🗂️ZIP Manager Guide ✅Code Validator Guide 🛡️Encryptor / Decryptor Guide 🧪Mouse & Keyboard Tester Guide 📶Internet Speed Test Guide 🎡Wheel Spinner Guide 🏠Mortgage Calculator Guide 📈Compound & Simple Interest Calculator Guide 💼Salary Converter Guide 💳Debt Payoff Calculator Guide 🧾Invoice Generator Guide 🏖️Retirement Calculator Guide 📉Inflation Calculator Guide ⏱️Timesheet Calculator Guide 🎥Screen Recorder Guide 📡Internet Connection Monitor Guide 🔊Text to Speech Reader Guide 💪Health & Fitness Calculator Guide ⏱️Online Timer & Stopwatch Guide 💱Currency Converter Guide 📏Unit Converter Guide 🧾Sales Tax, Discount & Margin Calculator Guide

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