Free Web Tools
A directory of free online tools built by Hashito System Inc. Generate and analyze QR codes, create barcodes, check your browser information, clean up images, and visualize sorting algorithms, all with no install required and right in your browser.
Most used tools Ranked by measured page views over the last 90 days
QR Code Analyzer
Upload a QR code to analyze and display detailed information such as its error-correction level, version, and mask pattern.
QR Code Generator
Generate QR codes from URLs or text. Fine-tune the error-correction level, version, size, margin, and color, then download as PNG or SVG.
QR Code EC Tester
Visually test the limits of each error-correction level by masking parts of a QR code to find its readable boundary.
QR Code Photo Restore
Auto-repair QR codes that won't scan: the module grid is estimated from the finder patterns and every module is repainted by majority vote. Enhancement and an auto-retry sweep included. Runs entirely in your browser — images are never uploaded.
WiFi QR Code Generator
Generate a Wi-Fi QR from SSID and password. Scan with a phone camera to connect.
Japanese Phone Number Generator
Randomly generate Japanese phone numbers (mobile, landline, toll-free). Hyphen on/off and CSV export.
Sort Image Visualizer
Upload an image and experience sorting algorithms in motion through sight and sound. Supports 8 different algorithms.
Manuscript Paper Sheet Counter
Convert a character count into 400-square and 200-square Japanese manuscript paper (genkoyoshi) sheets. Shows characters and lines; spaces optional.
QR & Barcode 19 tools
Generate, analyze and restore QR codes and barcodes for URLs, Wi-Fi, contacts and more. QR & Barcode page →
QR Code Analyzer
Upload a QR code to analyze and display detailed information such as its error-correction level, version, and mask pattern.
QR Code Generator
Generate QR codes from URLs or text. Fine-tune the error-correction level, version, size, margin, and color, then download as PNG or SVG.
QR Code EC Tester
Visually test the limits of each error-correction level by masking parts of a QR code to find its readable boundary.
QR Code Photo Restore
Auto-repair QR codes that won't scan: the module grid is estimated from the finder patterns and every module is repainted by majority vote. Enhancement and an auto-retry sweep included. Runs entirely in your browser — images are never uploaded.
WiFi QR Code Generator
Generate a Wi-Fi QR from SSID and password. Scan with a phone camera to connect.
Barcode Generator
Generate CODE128, EAN/JAN, UPC, CODE39, and other barcodes. Set bar width, height, color, and margin, then download as PNG or SVG.
SMS QR Code Generator
Generate an SMS QR code from a phone number and pre-filled message. Scanning opens a pre-filled SMS composer. PNG/SVG.
Email QR Code Generator
Generate a mailto QR code from an address, subject and body. Scanning opens a pre-filled email composer. PNG/SVG.
Contact QR Generator (vCard/MeCard)
Generate vCard/MeCard contact QR from name, phone, and email. Email, phone, and SMS QR supported. For business cards and email signatures.
Location (geo) QR Code Generator
Generate a location QR code (geo: format) from latitude and longitude. Scanning opens the point in a map app. PNG/SVG.
Calendar Event QR Code Generator
Turn an event title, date and location into an iCalendar (VEVENT) QR code. All-day events supported. PNG/SVG.
Bulk QR Code Generator
Paste one URL or text per line and generate up to 100 QR codes at once. Individual PNGs or one contact sheet.
Phone Number QR Code Generator
Generate a call QR code from a phone number. Scanning opens the dialer with the number filled in. PNG/SVG.
Calendar Event QR Code Generator
Generate an event QR from a title, date/time and location. Scanning opens an add-to-calendar screen. iCalendar, all-day, PNG/SVG.
Barcode Photo Restore
Recover barcodes that will not scan from a photo: scan lines are turned into brightness profiles, the module width is estimated from run lengths, and unreadable digits are filled in by a check-digit-validated search. Supports EAN-13/JAN, UPC-A, EAN-8, CODE128 and CODE39. Runs entirely in your browser.
QR Code Capacity Checker
Encodes your string and reports the version, module count and how many more characters still fit for each error correction level.
QR Code Print Size Calculator
Measures the version from your string and calculates the millimetres needed including the quiet zone, the module size and the pixel count at a given dpi.
MeCard QR Code Generator
Turn a name, phone number, email and address into a MeCard contact QR code. Shorter than vCard, so the version stays low.
UTM QR Code Generator
Attach utm_source, utm_medium and utm_campaign to a URL and turn it into a QR code so each flyer or poster is counted separately.
Text 20 tools
Count characters, compare differences, and convert case or character width in text. Text page →
Manuscript Paper Sheet Counter
Convert a character count into 400-square and 200-square Japanese manuscript paper (genkoyoshi) sheets. Shows characters and lines; spaces optional.
Kana to Romaji Converter
Convert hiragana and katakana to romaji in passport-style Hepburn or Kunrei-shiki.
Lorem Ipsum Generator
Generate Lorem ipsum placeholder text by paragraphs, sentences or words.
Slug Generator
Create URL-friendly slugs (hello-world) from text, with accent removal and separator options.
Reading Time
Estimate reading time from the word or character count of pasted text.
Character Counter
Paste text to instantly count characters (with/without spaces), words, lines, and bytes, with characters-to-words conversion tables (60, 160, 400 and more).
Case Converter
Convert text between camelCase, snake_case, kebab-case and more.
Full-width / Half-width Converter
Convert between full-width and half-width letters, symbols, katakana, and spaces by target. For normalizing form input and CSV. Runs in your browser.
Characters to Words
Convert characters to words and back, with presets and real-text measurement.
Japanese Dummy Text Generator
Generate Japanese dummy text (Japanese lorem ipsum) with kanji+kana, katakana, or hiragana — ideal for previewing Japanese layout.
Text Diff
Compare two texts and highlight added and removed lines.
Regex Tester
Test a regex against sample text with live match and group highlighting.
Line Tools
Sort lines, remove duplicates, drop blank lines and trim whitespace.
Line Sorter & Duplicate Remover
Sort text by line, remove duplicate lines, delete blank lines and trim spaces. Ascending/descending, case sensitivity and natural (numeric) order. Runs in your browser.
Newline Converter
Convert line endings between CRLF, LF, and CR, with detection and line count. Fixes Windows vs Unix/Mac and Git or editor warnings. Runs in your browser.
NATO Phonetic Alphabet Converter
Convert letters and digits into the NATO/ICAO phonetic code (Alfa, Bravo, Charlie…) for spelling out text clearly on the phone or radio.
Markdown Preview
Render Markdown to HTML instantly. Tables and code blocks supported, with one-click HTML copy.
Regex Visual Builder
Build a regex by connecting blocks, color-code matches in a test table, and read the meaning in a structure map.
Dummy Article HTML Generator
Generate article markup with headings, lists, quotes and tables to check how a CMS theme or article CSS handles real nesting.
Subtitle Timing Adjuster
Shift a whole SRT or WebVTT subtitle file forwards or backwards to fix out-of-sync captions. Converts between the two formats and rescales for frame rates, all inside your browser with no upload.
Encoding 10 tools
Convert between representations such as Base64, URL encoding, escaping and character codes. Encoding page →
Base64 Encode / Decode
Convert text to and from Base64. UTF-8 safe (Japanese, emoji) with optional URL-safe output.
Image to Base64 (Data URL)
Convert an image to a Data URL and get HTML/CSS embed snippets. Everything runs in your browser.
Unicode Code Point Inspector
List each character's code point (U+XXXX, decimal), UTF-8 bytes and UTF-16 (\uXXXX). See emoji surrogate pairs too. Runs fully in your browser.
Base58 Encode / Decode
Convert between text and Base58 (Bitcoin standard), dropping ambiguous 0, O, I, l and symbols. Runs in your browser.
URL Encode / Decode
Percent-encode and decode text for URLs — safe for Japanese and symbols.
HTML Escape / Unescape
Convert <, >, &, ", ' to and from HTML entities — handy for posting code.
Unicode Escape / Unescape
Convert text to and from \u3042-style Unicode escapes used in JSON, JavaScript and Java source. Runs in your browser.
Character Encoding Dump
See the UTF-8 bytes, Unicode code point and UTF-16 unit count of every character, plus a hex dump of the whole string.
JSON String Escape / Unescape
Escape text for a JSON string or unescape it back to text. Supports \uXXXX conversion for non-ASCII. Runs in your browser.
Base32 Encode / Decode
Convert between text and Base32 (RFC 4648, A-Z2-7), the case-insensitive scheme used for TOTP keys. Runs in your browser.
Data & Test Data 20 tools
Convert and format JSON, CSV and YAML, and generate dummy data for testing. Data & Test Data page →
Japanese Phone Number Generator
Randomly generate Japanese phone numbers (mobile, landline, toll-free). Hyphen on/off and CSV export.
Test Data Generator
Generate fictional test data — names, emails, phones, addresses, UUIDs — by count and columns. Export as CSV/TSV/JSON/SQL.
Japanese Name Generator
Randomly generate Japanese full names with furigana and romaji. Export sample names as test data by count to CSV.
JSON Formatter & Validator
Paste JSON to pretty-print or minify. Syntax errors are reported with line and column.
Japanese Address Generator
Randomly generate Japanese addresses (postal code, prefecture, city, block, building). Export as CSV for form checks.
CSV ⇄ JSON Converter
Convert between CSV and a JSON array, with header and delimiter options.
JSON Diff
Deep-compare two JSON documents and see added, removed, and changed keys with paths like a.b[2], color-coded. Key order is ignored; nesting is compared recursively.
Placeholder Image Generator
Create mockup placeholder images with a custom size, background and text colour. Save as PNG, JPEG or WebP.
Random Date Generator
Generate random dates for test data from a chosen range, count and format. Sorting and duplicate removal included.
YAML / JSON Converter
Convert between YAML and JSON in both directions. Syntax errors are shown with line and column numbers, and the indent width is selectable.
Email Address Generator
Randomly generate dummy email addresses for testing using safe reserved domains like example.com. Export to CSV.
JSON Relationship Map
Draws JSON nesting as levels. Select an element to color-code its parent, children, siblings and ancestors.
Dummy Company Name Generator
Randomly generate fictional Japanese company names in Japanese and English. Choose industry and legal entity type, export as CSV.
Test Barcode Number Generator
Generate batches of JAN/EAN-13, UPC-A, ISBN-13 and ITF-14 test codes with a correct check digit. In-store prefixes that cannot collide with real products are selectable.
.env and JSON Converter
Convert between a .env file and JSON. Handles comments, the export prefix, quoting, escapes and duplicate keys, and reports warnings.
CSV ⇄ Markdown Table
Convert CSV or TSV into a Markdown table and back, handling quoted commas, line breaks and pipe characters.
JSONL / JSON Converter
Convert between JSONL (NDJSON, one JSON per line) and a JSON array in both directions. Broken lines are reported with their line number.
JSON Schema Generator
Generate a JSON Schema (draft 2020-12) from sample JSON. Arrays are merged across every element; required and format inference are optional.
JSON to TypeScript
Paste JSON to generate TypeScript interfaces or types. Nested objects become separate named types and array element types are merged. Runs in your browser.
CSV to vCard (.vcf)
Build a vCard (.vcf) file from a contacts CSV. Name, phone, email, company and title columns are detected automatically and merged into one downloadable file.
Units, Numbers & Color 16 tools
Convert units and number bases, and calculate with colors, ratios and percentages. Units, Numbers & Color page →
Color Code Converter
Convert between HEX, RGB and HSL with a large live preview. Copy any notation in one click.
Number Base Converter
Convert between binary, octal, decimal and hex — accurate via BigInt.
Check Digit Calculator
Compute and verify the check digit for EAN-13/JAN, UPC-A, ISBN-13 and Luhn (credit cards). Enter a number and it validates the last digit too.
Kansuji Converter
Convert between Arabic numerals, Japanese kanji numerals, and formal daiji (壱弐参拾萬), including the money notation 金壱萬円也.
Contrast Ratio Checker
Check the contrast ratio between text and background colors and WCAG AA/AAA compliance. With color pickers and live preview.
Consumption Tax Calculator
Convert between tax-exclusive and tax-inclusive prices. Supports 10%, reduced 8% and custom rates.
Time Duration Calculator
Add and subtract HH:MM:SS durations across lines, with conversions to seconds, minutes, and hours.
Aspect Ratio Calculator
Find the aspect ratio (such as 16:9) from a width and height, or compute one dimension from a ratio and the other. Simplified with the greatest common divisor. Runs in your browser.
Roman Numeral Converter
Convert between Arabic numbers and Roman numerals (1-3999) with subtractive notation (IV, IX). Out-of-range or malformed input shows an error. Reference table included.
Percentage Calculator
What percent A is of B, A% of B, and the percent change from A to B — in three modes.
Data Size Unit Converter
Convert between B/KB/MB/GB (base 1000), KiB/MiB/GiB (base 1024), and bits. Understand storage vs OS display.
CSS Unit Converter
Convert px, rem, em, pt and % with configurable root and parent font sizes, so the rem/em difference is visible.
ISBN Converter (10 / 13)
Convert between ISBN-10 and ISBN-13 and verify the check digit. Shows the weights, sum and modulo so you can check the result by hand. Runs entirely in your browser.
Corporate Number Check Digit
Compute the check digit of a Japanese Corporate Number from its 12-digit body, or verify a full 13-digit number. Shows the odd and even digit sums. Runs in your browser.
Queue Simulator
Estimate wait time and utilisation from arrival rate, service time and server count, and compare server counts.
Work Hours Calculator
Total worked hours from clock-in, clock-out and breaks pasted one line per day, with 15-minute style rounding and overnight shifts.
Image & Video 15 tools
Convert formats, resize, and inspect or remove Exif data without uploading anything. Image & Video page →
Sort Image Visualizer
Upload an image and experience sorting algorithms in motion through sight and sound. Supports 8 different algorithms.
GIF Animator
Turn an image into a looping animated GIF with mosaic, shimmer, shake and move effects. Runs fully in your browser.
RAW Preview Extractor
Pull the embedded JPEG preview out of CR2, NEF, ARW, DNG and similar RAW files. No RAW decoder; everything runs in your browser.
PixelPurge
A free tool that merges fine color speckles and noise in AI-generated images into solid regions. It runs entirely in your browser, so your images are never uploaded.
Video to GIF
Convert MP4/WebM video to an animated GIF. Set frame rate, width and duration. GIF encoding runs entirely in your browser.
Image EXIF Editor
View, edit, and remove EXIF metadata (date taken, camera, GPS location) from photos. Strip location data before posting. Runs entirely in your browser.
Image Format Converter
Convert images between PNG, JPEG and WebP. Set quality and background color, and compare before/after sizes. Everything runs in your browser.
HEIC/HEIF Converter
Convert iPhone .heic images to JPEG, PNG or WebP. It ships no HEVC decoder and uses only built-in browser decoding, so it works in Safari only.
Images to PDF
Combine JPG, PNG and WebP images into a single PDF. Reorder pages, set paper size, orientation and margins. In-browser; images are never uploaded.
Circle and Line SVG Designer
Paste JSON made only of circles, lines and arcs to draw an SVG, export it as SVG or PNG, and copy a spec prompt for an AI.
Circle and Line Logo Maker
Draw guides with circles and lines, pick the enclosed regions to paint in JSON, and export the mark as SVG or PNG.
Movo Blocks (block-built image animation)
Stack blocks to animate a single image and export it as a WebM video. AI depth estimation and background removal run in your browser, and the image is never uploaded.
Face Blur
Find faces in a photo and hide them with blur, mosaic or a solid fill. Detection and editing run in your browser.
3D Model Viewer
Open STL, OBJ and glTF/GLB in your browser and measure triangles, size, volume and surface area.
Strip Mixer
Cut an image into even strips and deal every other strip into two new images. The direction alternates between vertical and horizontal each round, doubling the image count, with the recomposition animated. Runs in your browser.
Date, Time & ID 8 tools
Calculate and convert dates and times, and generate identifiers such as UUID and ULID. Date, Time & ID page →
UUID Generator (v1 / v4 / v7)
Bulk-generate v4 (random), v7 (time-ordered) and v1 UUIDs, up to 1000 at once. Also decodes a pasted UUID.
Date Difference Calculator
Show the difference between two dates and times as a Y/M/D H:M:S breakdown plus totals in each unit.
Unix Time Converter
Convert between Unix timestamps and dates: seconds/ms, time zone and ISO 8601.
Japanese Era (Wareki) Converter
Convert between Reiwa, Heisei, Showa, Taisho, Meiji and the Gregorian calendar. Era-change boundary dates are judged by exact date.
Cron Expression Parser
Explain a cron expression and compute the next run times. Supports weekdays, steps, ranges, and @daily macros.
ULID Generator
Bulk-generate 128-bit, time-sortable unique IDs (26-char Base32) as a UUID alternative. Cryptographic RNG, count and copy support.
Age Calculator
Get the exact age from a date of birth and reference date. Also shows kazoe age, days lived and days until the next birthday.
Time Zone Converter
Enter a date and time and see it as local time in major cities worldwide, with daylight saving time detected automatically.
Security 5 tools
Hash values, inspect JWT contents and generate passwords, all processed in your browser. Security page →
Password Generator
Generate strong random passwords with a secure RNG; choose length and character types, then copy.
JWT Decoder
Decode a JWT's header and payload and pretty-print claims like exp.
Hash Generator (SHA)
Compute SHA-1/256/384/512 hashes from text in the browser via Web Crypto.
Find the Source of a Hash
Find the value behind a hash by candidate-list matching or a constrained pattern search. SHA family, CRC32 and FNV-1a. Runs in your browser.
Basic Auth Header Generator
Build an Authorization: Basic header from a user name and password, with curl and fetch snippets, and decode Basic strings back.
Network & Web 9 tools
Investigate networks and the web: subnet calculation, URL parsing and HTTP status codes. Network & Web page →
Browser Info Viewer
A free tool that shows your browser type and version, screen/window size, IP, language, time zone, GPU, and more, all on one screen.
Subnet Calculator
From an IPv4 address and CIDR/mask, compute the network, broadcast, host range, and host count.
URL Parser
Break a URL into protocol, host, path, query parameters and hash. Parameters are percent-decoded and listed.
HTTP Status Codes
Look up what 200, 301, 401, 403, 404, 429 and 502 mean by number or name, with notes on 401 vs 403 and 301 vs 302.
MAC Address Generator and Formatter
Bulk-generate MAC addresses for testing and convert between colon, hyphen, Cisco dotted and plain notation. Locally administered bit and fixed OUI supported.
IPv6 Address Expander and Compressor
Convert IPv6 addresses between abbreviated and expanded form and normalize to the RFC 5952 recommended representation. Computes the network address and range from a prefix length.
Network Segment Designer
Assemble network segments as blocks and see parent-child relationships and IP ranges as a diagram. Overlaps and out-of-range CIDRs are flagged, and the design exports as Markdown.
Filter Syntax Checker
Explains what each ad blocker filter line blocks, flags mistakes, and tests which rules match a URL.
Punycode Converter
Convert internationalized domain names to and from Punycode (xn--) notation. Shows the result label by label and flags labels over the 63 octet limit.
Other 3 tools
Tools that do not fall into any of the categories above, such as physics simulators. Other page →
2D Fluid Simulator
Draw walls and watch water or wind flow in from the left and swirl around them. Fast currents and vortices change color.
Metal Stress Simulator 2D
Draw a metal shape on a grid, apply loads from the top and bottom, and see the stress distribution in shades of red. Steel, aluminum, rubber-like, and custom materials.
chmod Calculator
Convert between 755 and rwxr-xr-x, with special bits and a ready command.
No tools match.