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Text & writing

Character Counter

A free character counter with a large writing area, instant character, word, line and UTF-8 byte counts, plus local autosave.

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Whitespace & Line Break Cleaner

A free tool for cleaning line breaks, blank lines, spaces, and tabs. Compare the original and processed text side by side, with autosave, copy, and TXT download.

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Full-width & Half-width Converter

A free full-width and half-width converter for letters, numbers, symbols, spaces, and katakana, with side-by-side comparison, autosave, copy, and TXT download.

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Uppercase & Lowercase Converter

A free case converter for uppercase, lowercase, sentence case, title case, and inverted case, with instant conversion, autosave, copy, and TXT download.

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Word Frequency Counter

A free word frequency counter with frequency percentages, Japanese word segmentation, number exclusion, minimum length, and CSV copying.

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Text Difference Checker

A free text difference checker that highlights additions, deletions, and changes. Includes options to ignore spaces, line breaks, or letter case, plus autosave and text swapping.

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Safe Bulk Find & Replace

A free bulk find and replace tool with multiple rules, change previews, per-match exclusions, autosave, copy, and TXT download. All processing stays in your browser.

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Compare Two Lists

Compare two lists to find matches, differences, and all unique items. Choose case, whitespace, and blank-line options, then copy or download results as TXT.

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Invisible Character Detector & Remover

Find invisible Unicode characters and zero-width spaces, see their exact positions and names, then remove or convert only the types you choose. Runs locally in your browser.

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Duplicate Line Remover

A free duplicate line remover with options to ignore case and outer spaces, remove blank lines, sort results, copy, download, and autosave.

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Line & List Sorter

A free line and list sorter with alphabetical, natural numeric, and length sorting, plus trimming, blank-line removal, autosave, copy, and TXT download.

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Line Number Add & Remove

A free tool to add customizable line numbers or remove existing numbering, with start values, zero padding, separators, autosave, copy, and TXT download.

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Prefix & Suffix Each Line

A free tool to add a prefix and suffix to every line, including an {n} sequence placeholder, start number, blank-line skipping, autosave, copy, and TXT download.

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Line Filter & Extractor

A free line filter to keep or exclude matches using contains, starts with, ends with, exact match, or regular expressions, plus autosave, copy, and TXT download.

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Reading Time Calculator

Estimate reading time for English, Japanese, or mixed text with adjustable words-per-minute speed and character counts.

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Unicode Normalizer

Normalize text to NFC, NFD, NFKC or NFKD and compare code points and UTF-8 byte counts before and after conversion.

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Text Encoding Checker & UTF-8 Converter

Preview local TXT or CSV files as UTF-8, Shift_JIS or UTF-16, then save a new UTF-8 copy. Choose the encoding yourself; BOM evidence is shown separately.

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SRT / VTT Subtitle Time Shift

Shift SRT/VTT cue times together while preserving text, settings and line endings. Save adjusted subtitles as UTF-8.

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Placeholder Text Maker

Generate layout placeholder text with a chosen paragraph and sentence count.

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Selected Word Masker

List words to hide, one per line, and replace exact matches with mask characters.

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Character Separator

Insert a separator between grapheme clusters while keeping emoji sequences together.

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Character Code Point Inspector

Inspect each code point, UTF-8 byte length, and UTF-16 unit count.

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Morse Code Translator

Translate Latin letters and digits to International Morse code and back.

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Japanese Numeral Writer

Write integers from 0 to 9,999,999,999,999,999 in Japanese numerals or the supported formal financial forms.

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Text Line Decorator

Add combining strikethrough, underline, or overline marks to text.

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Text Progress Bar

Create a copyable text progress bar from completed and total counts.

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Calculators & converters

Percentage Calculator

Calculate percentages, proportions, and percentage changes in your browser. Handles decimals, negative values, and invalid input clearly.

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Discount Calculator

Calculate the final price and savings from an original price and discount percentage. Supports 0%, 100%, and decimal prices.

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Split Bill Calculator

Split a bill between people and optionally add a tip. See the amount per person, tip amount, and grand total instantly.

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Fuel Cost Calculator

Estimate trip fuel use and cost with km/L, L/100 km, or US MPG. No fuel-price API or external data is used.

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Electricity Cost Calculator

Estimate appliance energy use in kWh and electricity cost from wattage, daily hours, number of days, and your price per kWh.

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Unit Converter

Convert units for length, weight, temperature, area, volume, and speed, including metric, US customary, and Imperial labels.

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File Size Converter

Convert B, KB, MB, GB, TB, KiB, MiB, GiB, and TiB accurately, with decimal and binary units kept distinct.

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Aspect Ratio Calculator

Calculate an aspect ratio such as 16:9 and find a new width or height while preserving the original proportions.

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Number Base Converter

Convert whole numbers exactly between bases 2 and 36, including binary, octal, decimal, and hexadecimal, using BigInt.

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Statistics Calculator

Calculate mean, median, population and sample standard deviations, and weighted mean. Aggregate decimals exactly, then copy or save a JSON report.

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Fraction Calculator

Add, subtract, multiply, divide and simplify fractions exactly. Use large integers and negative fractions, then copy or save TXT and JSON results.

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GCD & LCM Calculator

Calculate the greatest common divisor and least common multiple of two or more integers exactly. Handle large integers, negatives and zero, then copy or save TXT and JSON.

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Combinations & Permutations Calculator

Calculate exact combinations (nCr) and permutations (nPr) when choosing r items from n without repetition. Copy or save the complete result as TXT or JSON.

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Ratio Allocation Calculator

Split a total across multiple ratios. Choose decimal places and distribute remainder units so allocations sum exactly to the total. Copy or save TXT and JSON.

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Slope & Grade Calculator

Calculate slope angle, percent grade and rise/run ratio from height change and horizontal distance in the same unit. Copy or save uphill and downhill results as TXT or JSON.

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Coordinate Distance Calculator

Calculate Euclidean distance between two points in 2D or 3D. Enter coordinates in the same unit, preserve large and decimal differences, then copy or save TXT and JSON.

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Circle and Sector Calculator

Calculate circle area, circumference, sector area and arc length from radius and central angle. View approximate results using pi, then copy or save TXT and JSON.

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Scale Calculator

Calculate real or drawing lengths from a 1:N drawing or map scale. Choose units for each length, then copy or save the calculation as TXT or JSON.

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Paper Size Comparison

Compare ISO A, JIS B, and Letter dimensions and calculate a fit-to-page scale.

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Fold Position Calculator

Calculate panel widths and fold positions for half, Z, and roll folds.

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Advertising Metrics Calculator

Calculate CTR, CPC, CVR, CPA, and ROAS from impressions, clicks, conversions, spend, and revenue.

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Print Campaign Break-even

Estimate gross profit and break-even sales from distribution, response rate, conversion rate, and profit per sale.

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Date & time

Date & Day Calculator

Calculate days between two dates or find the date a certain number of days before or after another date. Free and easy to use.

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Age Calculator

Calculate your age from your date of birth. Check your age on a specific date and see how many days remain until your next birthday.

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Work Hours Calculator

Calculate net working time from start time, end time, and break duration. Supports overnight shifts and decimal hours.

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Time Duration Calculator

Calculate the difference between two calendar date-and-time values. Time-zone changes and daylight-saving transitions are not included.

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Time Calculator

Add or subtract hours, minutes, and seconds from a time. Shows whether the result falls on the previous or following day.

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Business Days Calculator

Count business days between dates or add and subtract business days, excluding weekends and custom holidays.

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Stopwatch

Measure elapsed time with a browser stopwatch that supports pause, resume, laps, and reset without interval-counting drift.

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Countdown Timer

A timestamp-based countdown timer with hours, minutes, seconds, pause, resume, reset, and an on-screen completion notice.

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Pomodoro Timer

A simple Pomodoro timer with configurable work and break lengths, pause, resume, skip, and completed work-session count.

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Unix Timestamp Converter

Convert Unix timestamps to UTC ISO date-time values and convert ISO values back to seconds or milliseconds.

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Time Zone Converter

Convert local date and time between common IANA time zones using built-in Intl daylight-saving rules and no external API.

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Single Event ICS Generator

Create a timed or all-day event as a local ICS file. Set title, location and description without adding or sending it to a calendar.

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Images & PDF

Pro-ready

Image Compare & Diff

Compare two images with a slider, overlay, or pixel diff. Exact diff requires matching dimensions.

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Image Optimizer & Converter

Optimize and convert JPEG, PNG, and WebP images locally in your browser. Compare appearance and file size, process multiple images, and download them individually or as a ZIP.

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PDF Merge & Split

Merge multiple PDF files or extract selected pages for free. Your PDFs are processed entirely in your browser and are not uploaded.

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Image to PDF

Convert JPG, PNG, and WebP images to PDF directly in your browser. Combine multiple images into one PDF with no upload required.

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Image Cropper

Crop JPEG, PNG, or WebP images with free selection or 1:1, 4:3, 3:2, 16:9, and portrait presets, entirely in your browser.

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Image Metadata Viewer

Inspect filename, file size, dimensions, EXIF camera and lens data, capture date, orientation, and GPS presence locally.

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Image Color Picker & Palette

Pick colors from an image and copy HEX, RGB, HSL, or a palette of CSS variables.

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PDF to Image

Render PDF pages as JPG, PNG, or WebP images and download them individually or as a ZIP.

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PDF Page Organizer

Preview, reorder, rotate, and remove pages, then save a new PDF.

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Image Metadata Remover

Save a clean copy without location and other privacy metadata. Your original image stays unchanged.

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Print Size & PPI Calculator

Calculate an image’s PPI at a chosen print size, or find the pixels needed for a target PPI.

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Contact Sheet Maker

Arrange images in a contact sheet and export multiple pages as PNG, JPG, or PDF.

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Extract Images from PDF

Inspect embedded raster images in a PDF and save them as PNG files with page and size information.

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Seamless Tile Checker

Repeat a texture in a grid and zoom in to inspect its seams.

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Alpha & Transparency Checker

Switch backgrounds and inspect transparent, translucent, and opaque pixels.

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Texture Channel Pack & Unpack

Split and pack R, G, B, and A channels in 8-bit PNGs without color correction or resampling.

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PDF Visual Compare

Render selected pages from two PDFs and compare them with overlays, a slider, or flicker.

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Normal Map DirectX / OpenGL Converter

Convert between DirectX and OpenGL normal maps by inverting the green channel.

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Image Splitter

Split an image by rows, columns, or pixel dimensions and download the PNG tiles.

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PDF Page & Image Resolution Checker

Inspect PDF page count, page dimensions, orientation, and embedded raster image dimensions.

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Image Joiner

Join JPEG, PNG and WebP images horizontally or vertically at their original display dimensions. Reorder and align images, then save a PNG with transparent padding.

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PDF Page Numbers

Add page numbers to a PDF and save it. Choose a starting number, position, font size and margin, with an optional page range.

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PDF Text Extractor

Extract embedded PDF text in page order, then copy it or save a UTF-8 TXT file. This tool does not perform OCR on image-only PDFs.

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Image Redactor

Cover selected image regions with opaque black and save an original-size PNG. Use it to hide visible details such as names or addresses.

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Label Sheet PDF

Create a printable label sheet PDF with text, exact page dimensions, grid, spacing and starting position. Supports A4 and Letter.

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WAV Audio Trimmer

Trim uncompressed WAV audio by start and end time, locally in your browser. Preview and save the selected range as PCM16 WAV.

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Data & web

URL Encoder & Decoder

A free URL encoder and decoder for full URLs or components, with optional plus-space handling and autosave.

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Base64 Encoder & Decoder

A free Unicode-safe Base64 encoder and decoder with URL-safe output and optional line wrapping.

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JSON Formatter & Validator

A free JSON formatter and validator with 2-space or 4-space indentation, minification, recursive key sorting, clear errors, autosave, and copying.

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HTML Entity Encoder & Decoder

A free HTML entity encoder and decoder with optional quote and non-ASCII encoding.

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URL Slug Generator

A free URL slug generator with lowercase conversion, accent removal, Unicode preservation, separator choice, maximum length, autosave, and copying.

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URL Cleaner

Remove utm parameters, fbclid, gclid, and common email tracking parameters while preserving ordinary URL queries.

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CSV Viewer & Formatter

Parse CSV or TSV with quoted commas, escaped quotes, and multiline fields, preview it as a table, and export normalized CSV locally.

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Color Converter

Convert HEX, RGB, HSL, and alpha color values with a live preview, entirely in your browser.

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Contrast Checker

Calculate the WCAG 2.x contrast ratio for foreground and background colors and check AA and AAA text thresholds.

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Safe QR Code Generator

Create static QR codes for URLs, text, Wi-Fi, email, and phone numbers. Review the exact content first, then save as PNG or SVG—no signup and no built-in expiry.

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QR Code Reader

Read QR codes from uploaded images or a supported camera with local browser processing and no external decoding API.

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CSV Change Checker

Match old and new CSV rows by a key column and review added, removed and changed cells. Compare leading zeros and date formats as text.

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SHA-256 Hash Calculator

Calculate SHA-256 for text or files locally, then compare the result with an expected hash.

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UUID Generator (v4)

Generate 1–100 UUID v4 values, then copy individual IDs or save the whole list as TXT.

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CSV & JSON Converter

Convert CSV or TSV and JSON in your browser. Preserve text and large numeric digits, then copy or save the result.

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JSON Data Extractor

Extract a value by JSON key names or array indices. Preserve large numeric digits, then copy or save the result as JSON.

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JSON Structure Compare

Compare JSON keys, values and types to locate additions, removals and changes. Keep large numbers precise, then copy or save a JSON report.

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URL Query Builder

Build a URL query from keys and values. Keep repeated keys, append to or replace an existing query, then copy or save the URL as TXT.

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Batch File Renamer

Preview new names for multiple files and save renamed copies in a ZIP, preserving every original byte. Original files are unchanged.

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ZIP Creator and Extractor

Compress files into a ZIP or extract ZIP contents with size, path and integrity checks, entirely in your browser.

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Smooth Gradient Builder

Preview a two-color gradient and copy its CSS with your chosen angle.

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Base Color Palette

Build complementary, analogous, or triadic colors from a base color and copy the palette.

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Shadow CSS Builder

Adjust offsets, blur, spread, and opacity to create a card shadow.

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Button CSS Starter

Set colors, padding, and corner radius, then copy starter HTML and CSS for a button.

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Fluid Type Calculator

Calculate a CSS clamp() font size from two viewport widths and font sizes.

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Tint and Shade Samples

Create five color samples by mixing your base color with white and black.

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Ruby HTML Builder

Enter base text and a reading to generate escaped HTML ruby markup.

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Filename Rename Planner

Plan sequential filenames and export an old-to-new mapping without changing files.

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Random & handy

Secure Password Generator

Generate a strong random password for free. Choose password length, uppercase, lowercase, numbers and symbols. Runs entirely in your browser.

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Roulette & Random Picker

Enter names or options and pick one at random for free. Use this simple roulette for speaking order, chores, meals, destinations, and more. No sign-up required.

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Random Number Generator

Generate random integers within a range, with or without duplicates, using crypto.getRandomValues and rejection sampling.

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Dice Roller

Roll up to 100 dice using d4, d6, d8, d10, d12, d20, or d100, with individual rolls, totals, and history.

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Team Generator

Enter one participant per line and create balanced random teams by number of teams or members per team.

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List Shuffler

Shuffle a list with crypto-based randomness while preserving every item and duplicate, then copy the full result.

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Rakuruno Games

Play browser games at Rakuruno Games.

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