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Images42

Image to C Array Halftone Generator Merge images Flip image Add text to image Invert colors Crop image Image mosaic SVG → PNG Image → ICO JPG → WebP Resize images PNG → WebP HEIC → JPG HEIC → PNG JPG → PNG PNG → JPG JFIF → JPG GIF → PNG TIFF → JPG PNG → SVG WebP → JPG WebP → PNG AVIF → PNG AVIF → JPG Image → pixel art Image compression Black & white photo Drawing grid Image color picker Cross Stitch Pattern Maker Bead pattern maker Image → Base64 Base64 → image Image to text GIF maker Meme generator Blur image Add watermark Image splitter SVG to JPG EXIF viewer

PDF tools26

Printable Label Sheet Generator Envelope Template Generator PDF Booklet Maker PNG → PDF Merge PDF Split PDF PDF → JPG PDF → PNG PDF OCR Rotate PDF Delete PDF pages JPG → PDF Word to PDF Sign PDF Protect PDF Unlock PDF Organize PDF Add Page Numbers Watermark PDF PDF to Text File to Markdown HTML to PDF Markdown to PDF TXT to PDF PDF Metadata Invoice Generator

Encoders & decoders54

Encoding & Encryption Tools ↗JavaScript Encoder / Decoder Email Obfuscator htpasswd Generator MySQL Password Hash PostgreSQL MD5 Password Hash MariaDB Password Hash Bcrypt Generator Bcrypt Verifier CRC-16 Hash Calculator AES Encrypt / Decrypt DES Encrypt / Decrypt Escape Encoder / Decoder Keccak Hash Calculator MD4 Hash Calculator MD2 Hash Calculator RSA / RSA2 Encrypt / Decrypt Scrypt Generator Scrypt Verifier SHAKE Hash Calculator Cisco Type 7 Encoder / Decoder SM2 Encrypt / Decrypt SM3 Hash Calculator SM4 Encrypt / Decrypt Punycode Encoder / Decoder Token Random Generator JSON Key Random Generator RC4 Encrypt / Decrypt Rabbit Encrypt / Decrypt Hash Calculator Triple DES (3DES) Encrypt / Decrypt RIPEMD-160 Hash Calculator Base64url Encoder / Decoder Unicode Code Point Converter Hex Byte Order Reverser SHA Hash Generator JWT Decoder Text to Binary Converter Text to Hex Converter JSON String Escape / Unescape Base32 Encoder / Decoder Base58 Encoder / Decoder HMAC Generator CRC32 Calculator MD5 Text Hash GZIP Text Compressor JWT Key Generator Escape Regex Metacharacters Morse Code Translator Unicode Escape Converter ROT13 Text Converter URL Encoder / Decoder Base64 Encoder / Decoder HTML Escape / Unescape Random Password Generator

Text tools40

SRT to VTT Converter Guitar Chord Transposer Terbilang Converter (Indonesian Number to Words)Thai Baht Text Converter (Numbers to Thai Words)Vietnamese Number to Words Converter Remove Vietnamese Accents Online Thai Keyboard Layout Fixer Turkish Character Converter (ş ğ ı to ASCII)Speech to Text Text List Set Operations Extract URLs from Text Shuffle Text Lines Sort Lines Reverse Text Find and Replace Text Remove Whitespace HTML to Plain Text Markdown to Plain Text Naming Case Converter URL Slug Generator Add / Remove Line Numbers Add Prefix / Suffix to Lines Text Frequency Counter Filter Text Lines Remove Empty Lines Extract Text Column Wrap Text Lines Indent / Unindent Text Truncate Text Split Text into Chunks Clean Email List Character Counter — Count Characters, Words & Lines Online Lorem Ipsum Generator — Paragraphs, Sentences, Words Typing test Fancy text Markdown editor Uppercase / Lowercase Converter Remove Duplicate Lines Remove Line Breaks Text Diff Checker

Language & scripts8

Hiragana / Katakana Converter Fullwidth / Halfwidth Converter Number to Words Converter — Amounts in Words in 20 Languages Text → Speech Cyrillic to Latin Transliteration — Passport, GOST 7.79, Ukrainian Keyboard Layout Fixer — Convert Text Typed in the Wrong Layout (ghbdtn → привет)Korean Romanization — Hangul to English Letters (Revised Romanization)Romaji Converter — Hiragana & Katakana to Hepburn Romaji (Passport Style)

Date & time24

Snowflake ID Decoder Unix Timestamp Converter Business Day Calculator Date Difference Calculator Age Calculator Duration Calculator Batch Timestamp Converter Timestamp Unit Converter Timestamp Difference Calculator Time Zone Converter Add / Subtract from Date ISO Week Date Converter Day of Year Converter Excel Serial Date Converter Windows FILETIME Converter Unix Timestamp Converter Cron Expression Generator & Explainer — Next Run Times Countdown timer Stopwatch Pomodoro timer Thai Buddhist Era Converter (BE and CE)Vietnamese Lunar Calendar Converter Hijri Gregorian Date Converter — Umm al-Qura Calendar Japanese Era Converter — Wareki (Reiwa, Heisei, Showa) to Western Year

Calculators & units35

Resistor Color Code Calculator LED Series Resistor Calculator DPI Calculator Capacitor Code Calculator STL Viewer Plywood Cut Calculator German VAT Calculator (MwSt 19 % and 7 %)Rule of Three Calculator (Dreisatz with Steps)Spain and Mexico IVA Calculator Spin the wheel Yes or no wheel Number wheel Letter wheel What to eat wheel Name picker Dice roller Flip a coin BMI calculator Random Integer Generator Scientific Notation Converter Bitwise Calculator Roman Numeral Converter Percentage Calculator Ratio Simplifier Fraction Calculator Data Size Converter Length Converter Temperature Converter Number List Statistics Mass Unit Converter Area Unit Converter Volume Unit Converter Speed Unit Converter Angle Unit Converter Duration Unit Converter

Learning & printables16

Telling Time Worksheet Generator Fraction Worksheet Generator Word Search Generator Printable Maze Generator Printable Flashcard Maker Arithmetic Worksheet Generator Vertical Arithmetic Worksheet Generator Multiplication Table Worksheet Generator Chinese Copybook Generator Calligraphy Practice Paper Generator Pinyin Practice Sheet Generator Name Tracing Worksheet Generator Hiragana & Katakana Practice Sheets Hangul Practice Sheet Generator Pen Control Tracing Worksheets Printable Graph Paper Generator

Validators4

IBAN Validator — Check IBAN Numbers Online (Batch)DNI / NIE Letter Calculator — Validate Spanish NIF and NIE CPF / CNPJ Validator and Generator — Including Alphanumeric CNPJ PESEL / NIP / REGON Validator — Check Polish ID and Tax Numbers

CSV & tables12

CSV to PDF CSV to HTML Table CSV to SQL INSERT Remove Duplicate CSV Rows CSV / TSV Converter CSV to Markdown Table Transpose CSV Select CSV Columns Sort CSV Rows CSV Column Statistics JSON → CSV CSV → JSON

JSON42

JSON Diff Checker JSON to Typed XML Converter Sort JSON Keys JSON Merge Patch JSON Pointer Lookup Flatten JSON JSON to NDJSON NDJSON to JSON JSON to SQL INSERT JSON to Query String Query String to JSON Sort JSON Array Filter JSON Array Remove JSON Array Duplicates JSON to Markdown Table JSON to Python Literal JSON to PHP Array Extract JSON Key Paths JSON Editor jq Playground JSON → React PropTypes JSON → Flow JSON → GraphQL JSON → TypeScript JSON → MobX-State-Tree Model JSON → Sarcastic JSON → io-ts JSON → Rust Serde JSON → Mongoose Schema JSON → Big Query Schema JSON → MySQL JSON → Scala Case Class JSON → Go Struct JSON → Go Bson JSON → YAML JSON → JSDoc JSON → Kotlin JSON → Java JSON → JSON Schema JSON → TOML JSON → Zod Schema JSON formatter

JSON Schema5

JSON Schema Validator JSON Schema → TypeScript JSON Schema → OpenAPI Schema JSON Schema → Protobuf JSON Schema → Zod Schema

JSON-LD6

JSON-LD → N-Quads JSON-LD → Expanded JSON-LD → Compacted JSON-LD → Flattened JSON-LD → Framed JSON-LD → Normalized

Formatters & config16

XML Formatter YAML Formatter TOML Formatter CSS Formatter SQL Formatter JavaScript Formatter HTML Formatter JSON to ENV ENV to JSON INI to JSON JSON to INI XML → JSON YAML → JSON YAML → TOML TOML → JSON TOML → YAML

SVG4

SVG Path Editor SVG Optimizer SVG → JSX SVG → React Native

HTML3

HTML → JSX HTML → Pug Markdown → HTML

CSS14

Flexbox Generator CSS Clip Path Generator Box Shadow Generator CSS Grid Generator Cubic Bezier Generator Border Radius Generator Glassmorphism Generator CSS Gradient Generator CSS → JS Objects CSS → template literal CSS → TailwindCSS Less → CSS Scss → CSS Sass → CSS

JavaScript1

JavaScript → JSON

TypeScript5

TypeScript → Flow TypeScript → TypeScript Declaration TypeScript → JSON Schema TypeScript → plain JavaScript TypeScript → Zod Schema

Flow3

Flow → TypeScript Flow → TypeScript Declaration Flow → plain JavaScript

GraphQL9

GraphQL → TypeScript GraphQL → Flow GraphQL → JAVA GraphQL → Resolvers Signature GraphQL → Introspection JSON GraphQL → Schema AST GraphQL → Fragment Matcher GraphQL → Components GraphQL → TypeScript MongoDB

Developer tools51

Online Python Compiler Online JavaScript & TypeScript Compiler Online SQL Editor (SQLite / PostgreSQL)Online Lua Compiler Online HTML Editor with Live Preview Online Go Compiler Online C Compiler Online C++ Compiler Mermaid Live Editor Code to Image cURL Converter HTTP Headers to JSON Cookie Parser UTM Campaign URL Builder robots.txt Generator HTML Meta Tag Generator Chmod Permission Calculator IPv4 Range to CIDR Number Base Converter HEX / RGB / HSL Converter UUID v4 Generator Certificate Decoder URL Parser Semver Checker IPv4 and Integer Converter IPv4 Subnet Calculator IPv6 Expand / Compress CIDR and Netmask Converter JWT Generator and Signer JWT Signature Verifier JWT Claims Checker URL Builder Extract URL Slug UUID Inspector Color Contrast Checker PX / REM Converter CSS Clamp Generator Compress video Audio Converter Video Converter MP4 → MP3 MOV → MP4 WEBM → MP4 WAV → MP3 M4A → MP3 Video to GIF Cadence → Go QR Code Generator QR code scanner Barcode generator Regex tester

Layout & Safe Areas1

iPhone Safe Area Simulator & CSS Generator

IPv4 Range to CIDR

Cover inclusive start and end IPv4 addresses with the smallest aligned CIDR blocks, without extra addresses.

Input

Start IPv4

End IPv4

Result

Type or paste on the left — the result updates as you type.

Cover inclusive start and end IPv4 addresses with the smallest aligned CIDR blocks, without extra addresses.

Up to 100,000 UTF-16 units per input and 1,000,000 per result. See the supported formats and examples below.

Related tools

Chmod Permission CalculatorConvert three-digit octal permissions and nine-character rwx notation. Special permission bits are not supported.IPv4 Subnet CalculatorCalculate network, netmask, host range and address counts from IPv4 CIDR.CIDR and Netmask ConverterConvert an IPv4 prefix length into a dotted netmask and back.

Format references

RFC 4632 — CIDR

Tool page updated: 2026-09-27

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Image tools

Image compression
HEIC → JPG
WebP → JPG
Resize images

Image tools

PDF tools

Merge PDF
Split PDF
PDF → JPG
JPG → PDF

PDF tools

Data & formats

JSON Editor
JSON → CSV
CSV → JSON

JSON tools
CSV & tables
Formatters & config

Text tools

Character Counter — Count Characters, Words & Lines Online
Text Diff Checker
Remove Duplicate Lines

Text tools

Language & scripts

Number to Words Converter — Amounts in Words in 20 Languages
Text → Speech
IBAN Validator — Check IBAN Numbers Online (Batch)

Language & scripts
Validators

Code & development

JSON → TypeScript
HTML → JSX
TypeScript → plain JavaScript

HTML tools
JavaScript tools
GraphQL
Developer tools
Layout & Safe Areas

Encoders & decoders

Base64 Encoder / Decoder
URL Encoder / Decoder
AES Encrypt / Decrypt

Encoders & decoders

Date, time & calculations

Unix Timestamp Converter
Date Difference Calculator
Percentage Calculator

Date & time
Calculators & units

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