Calculator
Evaluate expressions, track history, and handle quick arithmetic without leaving the page.
- Expression input
- Recent history
- Copy result
Client-side utility collection
One place for privacy-first browser tools.
Fast client-side utilities for text, numbers, dates, images, PDFs, and developer workflows. Everything runs in your browser.
Routes, navigation, RSS, and sitemap are generated from a single tool registry.
Tool catalog
81 browser utilities, ready for more.
Unit Converter
Convert between common length, weight, area, volume, speed, and temperature units.
- Six categories
- Swap units
- Formula hint
Currency Converter
Convert major currencies using a local offline rate snapshot you can edit and store in the browser.
- Offline rates
- Editable snapshot
- Reverse rate
Date Calculator
Compare dates, count days, and add or subtract precise offsets from a base date.
- Date difference
- Offset planner
- Weekday count
Timezone Converter
Compare two time zones and preview meeting times across major cities.
- Zone conversion
- World clock
- Browser local time
Timestamp Converter
Convert Unix timestamps into local or UTC time and turn readable dates back into seconds or milliseconds.
- Auto detect units
- UTC and local output
- Now shortcut
ICS Event Generator
Create calendar event files locally with timezone-aware scheduling, reminders, guests, and recurrence presets.
- Timed or all-day events
- Recurrence and reminders
- Guest-ready .ics download
Cron Expression Builder
Build, validate, and explain 5-field cron expressions with upcoming run previews.
- 5-field validation
- Upcoming run preview
- Preset schedules
QR Generator
Create QR codes locally with custom size, colors, margin, and downloadable SVG or PNG output.
- SVG export
- PNG export
- Color controls
Barcode Generator
Create Code 128, EAN-13, and UPC-A barcodes locally with validation, batch rows, and SVG or PNG export.
- Three barcode formats
- Batch validation and preview
- SVG and PNG download
Password Generator
Generate multiple strong passwords with configurable character sets and instant strength hints.
- Crypto RNG
- Batch suggestions
- Entropy estimate
JWT Decoder
Decode JWT header and payload locally, inspect common claims, and preview token timing without verification.
- Header and payload decode
- Claim timing preview
- Bearer token cleanup
JWT Builder & Verifier
Create HMAC-signed JWTs locally, edit claims, and verify pasted tokens against the same shared secret.
- Claim presets and timestamp helpers
- HMAC signing and signature verification
- Bearer and cURL output
HMAC Generator
Sign messages locally with HMAC, switch encodings, verify expected signatures, and preview prefixed headers.
- Message and secret encodings
- Expected signature compare
- Prefixed header preview
UUID Generator
Generate single or batched UUID v4 values and copy them in the format you need.
- Batch generation
- Uppercase option
- Hyphen toggle
Hash Generator
Hash text or files locally with standard SHA algorithms and compare against an expected digest.
- Text and file input
- Digest compare
- Multiple SHA variants
Regex Tester
Test regular expressions against sample text with flags, group capture details, and replace previews.
- Live test run
- Group capture table
- Replace preview
JSON Formatter
Validate, format, minify, and recursively sort JSON while tracking payload stats.
- Pretty print
- Minify
- Sort keys
JSON Path Explorer
Inspect JSON structure locally, inventory every field path, search nested values, and copy exact node paths.
- Path inventory
- Search and filter
- Node detail inspector
JSON to TypeScript
Generate TypeScript types from JSON locally with optional-field inference, naming controls, and path-level audits.
- Interface or type alias output
- Optional field and union inference
- Path audit with copy actions
SQL Formatter
Format SQL locally, switch keyword casing, preview structure, and inspect query metadata without sending queries anywhere.
- Multi-statement formatting
- Keyword and identifier casing
- Statement and table insights
CSV to JSON
Convert CSV or TSV rows into JSON objects locally with header-based keys and copy-ready output.
- CSV or TSV input
- Header-based objects
- Pretty or minified export
JSON to CSV
Turn JSON arrays into CSV locally with nested key flattening, field selection, and spreadsheet-ready downloads.
- Nested key flattening
- Column selection
- CSV preview and download
Text Diff Checker
Compare two text blocks line by line, spot additions or removals, and copy the filtered output you need.
- Line-by-line compare
- Change counters
- Copy filtered output
Base64
Encode or decode UTF-8 text and files, with optional URL-safe output and data URL support.
- UTF-8 safe
- File encode
- URL-safe mode
Data URL Builder
Create, inspect, preview, and decode data: URLs locally from text or files with ready-to-paste embed snippets.
- Text or file input
- Live media preview
- HTML, CSS, and decoded export
URL Encoder
Encode, decode, and inspect URL query parameters without sending data anywhere.
- Encode/decode
- Parameter parser
- Query preview
UTM Builder
Build campaign URLs locally, preserve existing query parameters, and validate UTM naming before sharing.
- Channel presets
- Existing query preservation
- Recent template storage
Mailto Link Builder
Create prefilled email links locally with recipients, subject, body templates, and copy-ready snippets.
- Recipient and body fields
- Live draft preview
- URL, HTML, and Markdown copy
Email Subject Line Tester
Draft subject lines locally, preview inbox clipping, flag risky wording, and tune the paired preheader before you send.
- Mobile and desktop inbox previews
- Length and merge-tag audit
- Spam-risk and repetition checks
vCard Generator
Create shareable contact cards locally with live previews, QR export, and downloadable .vcf files.
- Live contact preview
- QR code export
- .vcf download and copy
Social Card Preview
Draft Open Graph and Twitter card metadata locally with live previews, snippet output, and launch checks.
- Open Graph and Twitter tags
- Large and compact card previews
- Metadata quality checklist
Meta Tag Generator
Draft page title, description, canonical, robots, and social metadata with live SERP and card previews.
- Title and description audit
- SERP and social previews
- Ready-to-paste head tags
Schema Markup Generator
Build JSON-LD for articles, FAQs, products, events, and organizations with live previews and launch checks.
- Five schema templates
- JSON-LD and script output
- Validation checklist
Hreflang Builder
Build hreflang clusters locally, generate HTML or HTTP header output, and audit pasted alternate tags for gaps.
- HTML, HTTP, and sitemap output
- Locale and host validation
- Pasted tag audit
robots.txt Generator
Draft robots.txt rules locally with presets, multi-bot groups, sitemap links, and path match previews.
- Preset policies
- Path match tester
- Copy and download output
XML Sitemap Builder
Build XML and TXT sitemaps locally, normalize large URL lists, and audit duplicates or weak page coverage before launch.
- XML and TXT sitemap output
- URL normalization and duplicate audit
- Section coverage and priority hints
Readability & SEO Checker
Audit content clarity, reading grade, keyword density, and SERP snippet length from one local workspace.
- Readability score and grade
- SERP snippet preview
- Sentence and keyword audit
Delimiter Studio
Split pasted values, clean and deduplicate them, then export lines, CSV, JSON arrays, or SQL IN lists locally.
- Auto delimiter detection
- Deduplicate and sort
- SQL and JSON export
HTTP Header Analyzer
Parse raw request or response headers locally, inspect security and cache signals, and review cookie or CORS details.
- Request or response parsing
- Security and cache checklist
- Cookie and CORS insights
Text Case Converter
Transform text into common writing and developer naming styles with one click.
- Prose styles
- Dev naming styles
- Copy any result
Text Line Toolkit
Sort, shuffle, filter, trim, and deduplicate pasted lines locally with a duplicate report and export-ready output.
- Sort and shuffle modes
- Duplicate strategy controls
- Filter and export output
Markdown Table Generator
Build Markdown tables visually, paste CSV or TSV, and import JSON rows without leaving the browser.
- Visual editor
- CSV or TSV paste
- JSON rows import
Markdown Preview
Write Markdown locally with live preview, heading outline, document stats, and copy-ready HTML output.
- Live rendered preview
- Heading outline
- HTML export and download
Lorem Ipsum Generator
Generate placeholder paragraphs, sentences, or words locally for mockups, docs, and content drafts.
- Paragraph, sentence, or word mode
- Classic opening toggle
- Copy or TXT download
Word Counter
Count words, lines, characters, reading time, and repeated keywords as you type.
- Live stats
- Reading time
- Top keywords
BMI Calculator
Calculate BMI in metric or imperial units and view healthy weight guidance for the same height.
- Metric and imperial
- Range label
- Healthy span
Percentage Calculator
Handle percentage-of, ratio, and percent-change calculations from one page.
- Three modes
- Percent change
- Quick answers
Interest Calculator
Calculate savings growth, compound interest, loan payments, total interest, and payoff schedules locally.
- Savings and loan modes
- Compound interest
- Monthly payoff schedule
Mortgage Calculator
Estimate mortgage payments, compare payoff scenarios, and inspect amortization details with taxes, insurance, PMI, and extra payments.
- All-in monthly payment
- Extra payment comparison
- Amortization schedule
Color Converter
Convert HEX, RGB, and HSL values instantly with a live preview and copy-ready output.
- HEX RGB HSL
- Live preview
- Quick palette
Color Contrast Checker
Check WCAG contrast ratios, preview real UI text, and generate accessible color alternatives locally.
- WCAG AA and AAA checks
- Live UI preview
- Accessible color suggestions
Color Palette Accessibility Lab
Build and audit a color palette locally with pairwise contrast checks, token previews, and color-vision simulations.
- Pairwise contrast matrix
- Color-vision simulation previews
- CSS variable and JSON export
CSS Gradient Generator
Build linear, radial, or conic gradients locally with multi-stop controls, live UI previews, and copy-ready code.
- Linear, radial, and conic gradients
- Multi-stop editor
- CSS and Tailwind export
Favicon Generator
Create favicon PNG sizes locally from text, emoji, or an uploaded image, then copy ready-to-use HTML and manifest snippets.
- Text, emoji, or image source
- Multi-size icon previews
- HTML and manifest snippets
MIDI Composer
Compose, edit, play, import, and download short MIDI patterns directly in the browser.
- Piano-roll editing
- Browser playback
- MIDI import and export
Image Resizer
Resize images locally with aspect-ratio controls, format selection, quality tuning, and download output.
- Aspect lock
- Format export
- Preview
Image Converter
Convert images between PNG, JPEG, and WebP locally with optional resizing and quality controls.
- Format conversion
- Optional resize
- Quality control
EXIF Viewer & Metadata Cleaner
Inspect photo metadata locally, flag GPS or device details, and download a cleaned image without EXIF.
- EXIF field inspection
- GPS and privacy risk flags
- Clean image export without metadata
Screen Defect Test
Check dead pixels, stuck pixels, backlight bleed, gradients, uniformity, sharpness, and color patterns in fullscreen.
- Fullscreen color cycle
- Bleed and uniformity checks
- Stuck-pixel flasher
Microphone Test
Test your microphone locally with live input level, frequency activity, clipping alerts, and a short recording preview.
- Device picker and permission flow
- Live waveform, spectrum, and level history
- Short recording preview and download
Monitor Response Test
Run a local moving target test for monitor response speed, ghosting, blur, and inverse ghosting checks.
- Adjustable px/sec
- Target gap comparison
- Fullscreen frame stats
PDF Merge
Combine multiple PDF files in the browser, reorder them, and download one merged document.
- Multiple files
- Reorder list
- Download merged PDF
Image to PDF
Turn JPG, PNG, or WebP images into a downloadable PDF locally with reorder controls.
- Multiple images
- Page size options
- Reorder and export
PDF Composer
Combine PDF pages and image files in one visual sequence, reorder pages, and export a new PDF.
- PDF page previews
- Add images
- Reorder mixed output
PDF Split
Extract selected page ranges from a PDF into a new document without uploading the file.
- Range extraction
- Page count preview
- Download result
PDF to JPG
Render PDF pages into downloadable JPG images directly in the browser.
- Page range selection
- Quality and scale controls
- Download each JPG
SVG Viewer & Optimizer
Inspect SVG markup, preview it safely, clean editor noise, and export a lighter responsive asset locally.
- Safe live preview
- Optimization controls
- Before and after stats
Subtitle Converter
Convert SRT and WebVTT locally, shift timestamps, renumber cues, and inspect subtitle timing before export.
- SRT and VTT conversion
- Millisecond timing shift
- Cue preview and stats
API Request Builder
Build API requests locally with headers, query params, auth helpers, and copy-ready cURL, fetch, or Axios snippets.
- cURL, fetch, and Axios output
- Header and query editors
- Auth and body presets
Aspect Ratio Calculator
Reduce ratios, scale widths or heights, compare common presets, and preview responsive frames locally.
- Ratio reduction and scaling
- Preset comparison
- Live frame preview and CSS snippet
IP Subnet Calculator
Analyze IPv4 CIDR blocks locally with subnet masks, usable ranges, binary breakdowns, and child subnet planning.
- CIDR and mask breakdown
- Usable host and range math
- Child subnet planner
SemVer Comparator
Compare semantic versions, test version ranges, and sort release lists locally with stable and prerelease insight.
- Version compare and diff labels
- Range tester with pass or fail results
- Sorted release list with stable insights
XML Formatter
Format, minify, validate, and inspect XML locally with structure stats and tag summaries.
- Pretty print and minify
- Validation status
- Tag and path insights
CSP Builder
Build Content Security Policy headers locally with presets, directive editors, risk checks, and copy-ready output.
- Policy presets and directive editor
- Risk checklist and source tester
- Header, meta, and report-only output
CORS Header Builder
Model cross-origin requests locally, generate CORS response headers, and audit risky policy combinations before shipping.
- Request simulator and preflight check
- Header policy builder with audits
- Express and Nginx output
Dotenv & INI Studio
Parse .env or INI files locally, audit duplicate keys, mask likely secrets, and export normalized JSON or shell snippets.
- .env and INI parsing
- Duplicate and secret audit
- JSON and shell export
Chmod Calculator
Convert Unix permission modes locally with octal and symbolic editing, special bits, and file or directory behavior notes.
- Octal and checkbox editing
- Special bits and command preview
- File and directory permission notes
Unicode Inspector
Inspect Unicode text locally with normalization previews, invisible character detection, code point tables, and byte counts.
- Normalization form comparison
- Invisible and bidi character audit
- Code point and UTF-8 analysis
CSV Audit Studio
Profile CSV or TSV data locally with column type inference, missing-value checks, duplicate detection, and top-value summaries.
- Delimiter and header detection
- Column quality profile
- Duplicate row and value summary
Slug Generator & Redirect Planner
Turn titles into clean slugs locally with batch processing, collision checks, URL previews, and redirect-ready mappings.
- Batch title processing
- Collision-safe slug planner
- URL preview and redirect map export