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UTILITY COLLECTION

Utilities

A collection of frequently used tools in one place. Quickly find what you need and browse utilities by category and group.

SEO & Blog Tools

A collection of blog and SEO optimization tools including meta tag generation, keyword analysis, title length checking, and more.

6

Basic SEO Checks

Analyze page titles and meta descriptions to improve search visibility and click-through rates.

Title / Description Length Checker Quickly check the character count, recommended length, and search result preview status of your blog title and description.

SEO Checklist Tools

Review essential SEO requirements and identify issues that may affect search engine visibility and indexing.

Canonical URL Checker Quickly check canonical tag issues in HTML head code, including missing tags, duplicate tags, href format, and absolute URL usage.
Blog SEO Checklist Check essential SEO items before publishing a blog post, including title, meta description, content structure, keywords, images, links, and mobile readability.
H1 / H2 Structure Checker Enter blog post HTML to quickly check H1, H2, and H3 heading structure, hierarchy issues, empty headings, and duplicate H1 usage.
Image Alt Checker Analyze image tags in blog post HTML and quickly check missing alt attributes, empty alt values, and filename-like descriptions.

SEO Analysis Tools

Analyze keyword density, content structure, readability, and on-page SEO performance.

Keyword Density Checker Analyze frequently used keywords and word repetition rates in blog post text to review SEO writing quality.

Developer Tools

A collection of developer productivity tools including Docker helpers, Nginx generators, configuration file builders, encoders, formatters, and validators.

10

Server Configuration Tools

Generate Docker Compose files, environment configurations, and deployment templates for servers and web applications.

Docker Compose Generator Select a project type and required services to generate docker-compose.yml, .env.example, Dockerfile, Nginx configuration, run commands, and a README draft at once.

Developer Analysis Tools

Analyze, test, and inspect JSON data, regular expressions, tokens, and other developer resources.

Regex Tester Enter a regular expression and test text to check matches, capture groups, and flag behavior in real time. Useful for validating emails, URLs, phone numbers, dates, hashtags, and code patterns.

Data Validation Tools

Validate, parse, and inspect JSON, YAML, XML, SQL, and other structured data formats.

YAML Validator Paste YAML code to check syntax errors, indentation issues, missing colons, array structure problems, and view the converted JSON result.

Automation Tools

Create, validate, and understand cron expressions, schedules, and task automation configurations.

Cron Expression Generator Create Cron expressions by combining minute, hour, day, month, and weekday fields, then check the schedule meaning and each field interpretation.

Time Conversion Tools

Convert Unix timestamps, epoch values, dates, and time formats for development and debugging.

Unix Timestamp Converter Convert Unix timestamps into dates and times, and check the current time in seconds, milliseconds, ISO format, UTC, local time, and KST.

Developer Conversion Tools

Convert HTML entities, encoded text, URLs, Base64 strings, and other developer data formats.

HTML Entity Encoder / Decoder Encode HTML special characters into entity codes or decode entity strings such as <div> back into readable text. Includes conversion statistics, copy, and TXT download support.

Developer Comparison Tools

Compare JSON, text, configuration files, and source code to identify differences and changes quickly.

JSON Diff Checker Compare two JSON datasets to find added, removed, and changed values. Useful for checking API responses, configuration files, and test data differences.
Text Diff Checker Compare two texts to check added, removed, and unchanged lines. Useful for reviewing differences in sentences, code, configuration files, and notices before and after edits.

Developer Generators

Generate UUIDs, JWTs, hashes, tokens, and other identifiers commonly used in development.

UUID v1/v4 Compare Generator Generate UUID v1 and UUID v4 at the same time and compare the differences between time-based and random-based UUIDs.
UUID Generator Generate random unique identifiers in UUID v4 format, customize case, hyphen usage, and output format, then copy or download the result as a TXT file.

Developer Tools → Formatter

Free formatting tools for SQL, JSON, HTML, CSS, and JavaScript. Clean up, beautify, and improve the readability of source code instantly.

7

Data Formatting Tools

Format, validate, beautify, and convert structured data formats such as JSON, XML, SQL, and YAML.

JSON Formatter Format or minify JSON data, validate syntax, and check object count, array count, key count, character count, and compression rate.
SQL Formatter Format complex SQL queries, convert keyword case, minify SQL, remove comments, check statistics, and download SQL files.

Developer Analysis Tools

Inspect, validate, analyze, and troubleshoot JSON, regular expressions, tokens, and developer data.

JSON Pretty Converter Format, minify, and validate JSON data directly in your browser. Use it to inspect API responses, clean configuration files, and debug development data.

Code Formatting Tools

Format, beautify, and minify HTML, CSS, JavaScript, SQL, and JSON code for improved readability and consistency.

HTML Formatter Format or minify HTML code, remove comments, and check tag count, line count, character count, and compression rate.
CSS Formatter Format or minify CSS code, remove comments, and check selector count, property count, character count, and compression rate.
JavaScript Formatter Format or minify JavaScript code, remove comments, and check function count, variable count, line count, character count, and compression rate.

Document Writing Tools

Write, edit, preview, and convert Markdown documents with real-time rendering support.

Markdown Preview Enter Markdown syntax and preview headings, lists, code blocks, tables, blockquotes, and links as HTML in real time. You can also copy or download the converted result.

Security Development Tools

A collection of security-focused development tools for password hashing, encryption, encoding, token analysis, and security validation commonly used during software development.

4

Authentication Tools

Generate and analyze JWTs, hashes, API tokens, and other authentication-related security data.

JWT Generator Enter Header, Payload, and Secret values to generate an HS256 JWT token and inspect its Header, Payload, and Signature structure at a glance.

Security Development Tools

Inspect, decode, and analyze tokens, authentication data, JSON payloads, and security-related information.

JWT Decoder Paste a JWT token to inspect its Header, Payload, and Signature structure. Check key claims, expiration time, and algorithm information directly in the browser.
Hash Generator Enter text to generate MD5, SHA-1, SHA-256, and SHA-512 hash values directly in your browser. The input is processed locally and is not sent to the server.
bcrypt Hash Generator Convert passwords or text into bcrypt hashes and quickly verify whether the original text matches a bcrypt hash directly in the browser.

SEO Development Tools

A collection of SEO development tools for generating robots.txt, sitemap.xml, meta tags, structured data, and other search engine optimization resources.

6

SEO Generators

Generate robots.txt files, XML sitemaps, meta tags, and other essential SEO resources.

robots.txt Generator Generate robots.txt content by entering crawler access rules, allowed paths, blocked paths, and a Sitemap URL.
sitemap.xml Generator Enter a list of site URLs to automatically generate a sitemap.xml file for search engine submission. You can copy the XML result or download it as a file.
Meta Tag Generator Enter a page title, description, URL, and featured image URL to generate SEO meta tags, Open Graph tags, and Twitter Card tags.

SEO Preview Tools

Preview Open Graph tags, social media cards, and link sharing appearance before publishing.

Open Graph Preview Enter a title, description, URL, and featured image URL to preview social sharing cards for KakaoTalk, Facebook, and X/Twitter, then generate OG/Twitter meta tags.

SEO Audit Tools

Analyze meta tags, Open Graph data, and SEO-related elements to improve search engine visibility.

SEO Head Checker Paste HTML head code to check title, description, canonical, robots, Open Graph, and Twitter Card tags in one place.

International SEO Tools

Generate hreflang tags and optimize multilingual websites for international search engines.

hreflang Generator Enter multilingual page URLs to automatically generate hreflang tags that tell search engines about alternate language versions of the same content.

Network Development Tools

A collection of network and server analysis tools for inspecting HTTP headers, CORS policies, cache settings, security responses, and web service configurations.

4

Developer Tools

Common encoding, decoding, and data conversion tools used in everyday development workflows.

Base64 Encoder / Decoder Encode plain text into Base64 or decode Base64 data back into readable text. Supports UTF-8 text, URL-safe conversion, auto conversion, result copy, and TXT download.
URL Encoder / Decoder Safely encode URL strings that contain Korean, spaces, and special characters, or decode encoded URL strings back to readable text. Supports query string analysis, auto conversion, URL component inspection, result copy, and TXT download.

Network Analysis Tools

Analyze HTTP responses, security headers, CORS settings, and web security configurations.

HTTP Header Analyzer Paste HTTP response headers to check security headers, cache policy, CORS settings, content type, and cookie security options in one place.
What Is My IP Address Check your current public IP address, browser, device, screen, language, and timezone information.

Design Development Tools

A collection of design and frontend development tools for creating CSS gradients, color palettes, UI styles, themes, and visual design resources.

10

Design Generators

Generate responsive CSS values, fluid typography, and modern UI design styles automatically.

CSS Clamp Generator Enter minimum size, maximum size, and viewport range to generate CSS clamp() values for responsive font-size, padding, margin, gap, and more.
CSS Gradient Generator Create linear-gradient, radial-gradient, and conic-gradient CSS background code by adjusting colors, direction, type, and color stop positions with a live preview.
CSS Animation Generator Adjust CSS animations such as Fade, Slide, Scale, Bounce, Pulse, and more with a live preview, then generate @keyframes and animation code instantly.
Border Radius Generator Adjust CSS border-radius values for cards, buttons, images, and modals with a live preview, then generate shorthand CSS, individual properties, and inline style code.
Box Shadow Generator Adjust CSS box-shadow values for cards, buttons, modals, and banners in real time, then generate natural SaaS-style shadow code and inline style examples.
Glassmorphism Generator Create glass-style Glassmorphism CSS by adjusting opacity, backdrop blur, border, radius, shadow, and preview the result in real time.
Color Palette Generator Create a Tailwind-style 50–900 color palette from a single base color, then export it as CSS variables, SCSS variables, or JSON for your design system.

Design Accessibility Checker

Analyze color contrast ratios and accessibility compliance based on WCAG guidelines.

Color Contrast Checker Calculate the contrast ratio between text and background colors and verify whether the combination passes WCAG AA and AAA accessibility standards.

Layout Builder

Visually design web page layouts and generate ready-to-use CSS Grid code.

CSS Grid Generator Test columns, rows, gap, minmax, auto-fit, and alignment options in real time, then generate CSS Grid code instantly.
Flexbox Playground Test justify-content, align-items, flex-direction, flex-wrap, gap, and align-content in real time, then generate CSS code instantly.

PDF Tools

A collection of PDF utilities for converting, merging, splitting, compressing, extracting images, extracting tables, and managing PDF documents efficiently.

5

PDF Conversion

Convert PDF pages into JPG or PNG image files quickly and easily.

PDF Image Converter Convert each page of a PDF file into PNG, JPG, or WebP images. Supports per-page image saving and ZIP bulk download for document capture, thumbnail creation, and file sharing.
Webpage to PDF Enter a webpage URL and generate a PDF based on desktop or mobile rendering. Adjust background printing, ad removal, header/footer removal, and rendering wait time to save the page in the format you need.

PDF Compression

Reduce PDF file size and save documents with optimized compression for easier sharing and storage.

PDF Compressor Reduce PDF file size by adjusting image quality and rendering resolution. Compress PDFs directly in your browser before sharing documents, attaching files to email, or uploading them to a website.
PDF Merge / Split Merge multiple PDF files into one document or split a single PDF by page or page range. Files can be processed in the browser, making it useful for organizing documents and managing submission-ready PDFs.

PDF Table Extraction

Extract tables and structured data from PDF files and convert them into Excel spreadsheets.

PDF Excel Table Extractor Extract table data from PDF documents and save it as CSV or Excel files. Analyze text-based PDF tables by page, preview the extracted results, and download the data.

Document Conversion

A collection of document conversion tools for converting PDF, Excel, CSV, JSON, Word, and other document formats quickly and efficiently.

1

Other

PDF Word Converter Convert PDF files to Word documents or Word documents to PDF. Select the conversion direction based on the uploaded file type and check the output file.

Data Conversion

A collection of data conversion tools for transforming Excel, CSV, JSON, XML, and other structured data formats quickly and accurately.

5

Other

Excel to CSV Converter Upload an Excel file, select the sheet you want, apply delimiter, trimming, and empty row removal options, then convert it into a CSV file for download.
CSV to Excel Converter Upload a CSV file, preview the data, apply delimiter, sheet name, and cleanup options, then convert it into an Excel file (XLSX) for download.
Excel to JSON Converter Upload an Excel file, convert the selected sheet or all sheets into JSON format, preview the data, then copy the result or download it as a JSON file.
CSV to JSON Converter Upload a CSV file, convert it into a JSON array, apply delimiter, header handling, trimming, and automatic type conversion options, then copy the result or download it as a JSON file.
JSON / XML Converter Convert JSON data to XML format or XML data to JSON format. Supports input validation, formatting, root tag settings, result copy, and file download.

Text Tools

A collection of text processing tools for writing, editing, analysis, formatting, content generation, and productivity enhancement.

6

Other

Text Counter Check the length of essays, blog posts, product copy, social bios and SEO snippets before you publish. Count characters, words, lines, sentences and bytes directly in your browser.
Comma Line Converter Split comma-separated tags, keywords, and option lists into one item per line, or join line-separated text into a clean comma list. Trim spaces, remove blanks, and remove duplicates in one pass.
Line Break Remover Replace awkward line breaks from PDFs, notes, and documents with spaces, remove them entirely, or keep paragraph breaks while cleaning line breaks inside each paragraph.
Space Remover Clean unnecessary spaces and tabs from copied documents, CSV text, notes, product names, and keywords. Trim text, collapse repeated spaces, remove all whitespace, or trim each line.
Special Character Remover Remove symbols, emojis, and special characters from text while keeping only the character types you need. Choose Korean, English, numbers, spaces, Japanese, or Chinese.
Password Generator Choose length and character types to generate a hard-to-guess random password. The password is generated in your browser with strength, entropy, and character set details.

Finance & Business

A collection of finance and business tools for loan calculations, investment returns, VAT calculations, labor cost estimates, settlements, and business operations.

6

Other

Loan Interest Calculator Estimate your monthly payment, total interest and repayment schedule from a loan amount, rate and term.
Man-Day Calculator Break a project into tasks, add difficulty and project buffers, then estimate final MD, delivery days, recommended staffing and cost. It is intended for early planning, internal review and quotation drafts before scope is finalized.
VAT Calculator Calculate tax-exclusive totals or split a tax-inclusive amount into net amount and tax.
Part-Time Wage Calculator Enter hourly wage and work hours, save work days on the calendar, and estimate this month's take-home pay. The tool is designed for safe editing, so selecting a saved date loads it for review instead of deleting it by accident.
Discount and Final Price Calculator Apply discounts, coupons, points, shipping and tax together to see the real checkout price and effective savings. It is useful when a store shows several promotions and you want to compare the actual amount you will pay.
Multi-Job Salary Calculator Track several part-time, freelance, weekend or platform jobs on one calendar and estimate monthly take-home pay, effective hourly income and goal progress. It helps compare jobs separately instead of mixing every income source into one rough total.

Converters & Calculators

A collection of practical calculators and conversion tools for quickly performing calculations, unit conversions, financial estimates, and everyday measurements.

3

Other

Unit Converter Convert length, weight, temperature, area, volume, speed, time, and data units with quick presets, a full conversion table, and recent history.
Pyeong Calculator Convert square meters and Korean pyeong, compare local square-foot presets, and estimate private and gross floor area for real-estate listings.
BMI Calculator Enter your height and weight to calculate BMI, check your weight category, and estimate a healthy weight range. You can switch between Asian and WHO standards, making it easier to compare everyday wellness references without changing tools.

Image, Photo & Graphics

A collection of image editing tools for compressing images, converting formats, resizing photos, cropping, and performing other image processing tasks quickly and easily.

8

Other

Image Compressor Compress JPG, PNG, and WEBP images directly in your browser. Uploaded files are not stored on the server, and original metadata such as EXIF is generally removed during compression.
Image Resizer Resize the width and height of JPG, PNG, and WEBP images. Keep the aspect ratio, use quick reduction presets, and adjust output quality and transparency.
Image Cropper Select an exact area from JPG, PNG, and WEBP images and save it as a new file. Use ratio presets, original-pixel coordinates, output quality, and transparency settings.
Image Background Remover Easily remove solid-color or light backgrounds and save the result as transparent PNG, WEBP, or JPG. Uploaded images are processed directly in your browser and are never stored on a server.
Image Format Converter Convert JPG, PNG, and WEBP images while adjusting dimensions, quality, and transparency. Everything is processed in your browser without uploading files to a server.
Image OCR Text Extractor Extract text from JPG, PNG, and WEBP images using OCR. Supports multiple images, grayscale conversion, contrast enhancement, scaling, result copy, and TXT or CSV download.
HEIC to JPG Converter Convert HEIC and HEIF images from iPhones and modern cameras into widely compatible JPG files. Adjust quality and maximum dimensions, then preview the result.
QR Code Generator Create QR codes for URLs, text, Wi-Fi, contacts, email, and SMS. Adjust colors and error correction, then save the result as PNG or SVG.

Time & Schedule Management

A collection of time tracking and scheduling tools including timers, stopwatches, D-Day calculators, date calculators, and productivity utilities.

6

Other

Stopwatch Measure elapsed time with centisecond precision. Record lap times, save recent measurements, and share stopwatch records using a link.
Timer An online countdown timer for studying, work, exercise, cooking, breaks, and Pomodoro focus sessions. Supports repeat timer, sound alerts, browser notifications, share links, and focus mode.
D-Day Calculator Select a base date and a target date to check D-Day, remaining days, elapsed days, weeks, and months at once. Saved schedules can be reviewed again in the same browser.
Date Difference Calculator Calculate the difference between two dates in days, weeks, months, and years. Useful for anniversaries, project schedules, contract periods, study plans, and work duration checks.
Age Calculator Enter a birth date to calculate full age, year age, Korean age, days lived, and days left until the next birthday.
Zodiac Calculator Enter a birth year or birth date to check your zodiac animal, Earthly Branch, zodiac order, and a short description.

Travel

A collection of travel planning tools including itinerary builders, travel expense calculators, currency converters, D-Day countdowns, and travel preparation checklists.

3

Other

Travel Itinerary Planner Create day-by-day tabs from your travel dates, then organize times, places, and notes in one practical workspace. Save, copy, and print your plan before the trip.
Travel Expense Splitter Enter trip members and shared expenses to calculate total cost, per-person share, individual balances, and suggested transfers.
Travel Exchange Calculator Estimate how much travel money you will receive after exchange rates and fees. Convert hotel, food, transport, and other trip budgets into your destination currency.

Random & Drawing

A collection of tools for fair and unbiased selections, including random pickers, team generators, roulette wheels, name draw tools, and lottery-style drawings.

5

Other

Name Picker Enter names one per line and randomly pick one or more winners. Use it for events, presentation order, role assignment, classroom activities, and simple draws.
Team Splitter Enter a member list, choose the number of teams, and create random teams online. Use gender balance, seed distribution, and automatic leader assignment for fairer groups.
Dice Roller Roll 1 to 6 dice online, choose quick presets for 1, 5, 10, or 100 rolls, and review the total, values, average, and recent roll history in one clean view.
Random Number Generator Generate random numbers within a custom range. Supports duplicate prevention, excluded numbers, multiple draws, and draw history.
Roulette Picker Enter options and spin an online roulette wheel to pick one at random. Useful for menus, giveaways, tasks, turns, and quick decisions.

Golf

A collection of practical golf utilities including golf handicap calculators, club distance tracking, score management, shot analysis, and golf-related tools.

9

Other

Golf Distance Estimator Estimate carry, roll, total distance and playing distance from ball speed, club speed, smash factor, launch angle and backspin. Add wind, turf, altitude and uphill or downhill adjustments for a practical club-selection reference.
Golf Penalty Picker Draw a random golf penalty from preset missions or your own custom list, then share it with your playing partners.
Golf Team Splitter Enter golf players and split them by random draw, gender balance, mixed groups or handicap balance. Useful for course rounds, simulator golf and club events.
Golf Tee Order Draw Choose the number of players and draw hidden sticks to decide the first tee hitting order fairly.
Golf Fortune Picker Draw a lighthearted golf fortune before your round. Check today's rhythm, a play tip and a short golf note, then share the result by URL or Kakao.
Golf Club Distance Table Record carry, roll and total distance for every club, then check where your yardage gaps overlap or open up.
Golf Round Cost Calculator Add green fees, cart fees, caddie fees, food and extras, then see each player's share and the payer reimbursement amount.
Golf Unit Converter Convert mph, m/s, yards and meters used in launch monitors, simulators and golf references. Enter ball speed and club speed to calculate smash factor automatically.
Golf Bet Calculator Enter hole-by-hole scores for a casual golf group and see the clean payment settlement instantly.