90 free tools · 100% client-side

Professional utilities. Zero data shared.

Every tool runs entirely in your browser. No account, no uploads, no telemetry. Just fast, private, professional-grade utilities.

🚫No account required
🔒Data stays in browser
Works offline
🆓Always free
Security & Privacy

DNS / DKIM Inspector

Fetch A, MX, TXT, and CNAME records live. Validate SPF, DKIM, and DMARC syntax instantly.

  • SPF / DMARC validation
  • Live DNS-over-HTTPS lookup
  • DKIM key parse
Security & Privacy

Subdomain Takeover Checker

Find subdomains that still point to deleted or decommissioned services — a common way attackers hijack forgotten subdomains.

  • Scans common subdomain names
  • Detects stale service pointers
  • No server required
Security & Privacy

CSRF Token Generator

Generate cryptographically-secure anti-CSRF tokens with configurable length in hex or Base64URL.

  • Cryptographically secure (browser-native)
  • Hex & Base64URL output
  • Usage code examples
Security & Privacy

SPF Record Creator

Build a valid SPF DNS TXT record by adding sending sources and choosing a policy.

  • 15+ provider presets
  • Policy selector
  • DNS setup instructions
Security & Privacy

DKIM Key Generator

Generate an RSA-2048 DKIM key pair in your browser. Get the DNS TXT record and PEM private key.

  • RSA-2048 / 1024-bit
  • DNS record ready
  • Private key download
Security & Privacy NEW

Password Strength Visualizer

See how long a modern GPU cluster takes to crack your password. Entropy, patterns, suggestions.

  • GPU crack-time estimate
  • Entropy analysis
  • Pattern warnings
Security & Privacy NEW

SSL/TLS Certificate Checker

Inspect SSL/TLS configuration via DNS. Checks CAA records, TLSA/DANE, DNSSEC, HTTPS redirect, and links to full grading reports.

  • CAA & TLSA/DANE records
  • DNSSEC + HTTPS redirect
  • Link to full SSL Labs report
Security & Privacy NEW

Hash Generator

Generate MD5, SHA-1, SHA-256, SHA-384, SHA-512 hashes from text or any file. HMAC support. Hex, Base64, Base64URL.

  • Text & file modes
  • HMAC support
  • Hex / Base64 / Base64URL
Security & Privacy NEW

Resume Anonymizer

Strip name, email, phone, address, LinkedIn, and GitHub from resume text for bias-free hiring reviews. For HR teams and recruiters.

  • 10 redaction types
  • Redaction log
  • Side-by-side preview
Security & Privacy NEW

JWT Decoder

Decode JSON Web Tokens instantly — inspect header, payload, expiry status, issuer, and audience. All client-side.

  • Header & payload decode
  • Expiry status & claims
  • Signature section
Security & Privacy NEW

Password Generator

Generate cryptographically secure passwords using window.crypto. Configure length, charset, and strength. Bulk mode included.

  • CSPRNG-backed
  • Length 4–256
  • Bulk generate + download
Security & Privacy NEW

Is It Down for Everyone?

Check if a website is down for everyone or just you. Tests DNS, TCP ports, and HTTP response from our servers in seconds.

  • DNS + TCP + HTTP check
  • Redirect chain trace
  • Local vs global diagnosis
Security & Privacy NEW

Email Address Validator

Validate email addresses for format, MX records, and disposable domains. Bulk-check up to 100 emails at once.

  • Format + MX record check
  • Disposable domain detection
  • Bulk 100 emails
Security & Privacy NEW

WHOIS & Domain Age Checker

Look up domain registration, registrar, creation date, expiry countdown, name servers, DNSSEC, and live DNS records via RDAP.

  • RDAP + live DNS lookup
  • Expiry countdown alert
  • DNSSEC + registrar info
Security & Privacy NEW

HTTP Headers Inspector

Inspect HTTP response headers from any URL. Check security headers, cache policy, redirect chain, and get a security score.

  • Security header score
  • Redirect chain trace
  • Cache & performance headers
Security & Privacy NEW

SSL Certificate Decoder

Paste a PEM certificate to decode Subject, Issuer, validity dates, SANs, key algorithm, and all extensions — parsed entirely in your browser.

  • Full X.509 field decode
  • SANs & extensions
  • Days-remaining countdown
Security & Privacy NEW

CORS Policy Tester

Test real CORS behaviour for any URL. Sends a simple request and an OPTIONS preflight, then shows every CORS header returned and a plain-English verdict.

  • Simple + preflight test
  • Allowed / blocked / open verdict
  • Full header dump
Security & Privacy NEW

CVSS Score Calculator

Calculate a CVSS v3.1 Base Score by selecting the 8 metric values — Attack Vector, Complexity, Privileges, Scope, CIA Impact. Severity badge and vector string included.

  • All 8 CVSS v3.1 metrics
  • Severity badge (None → Critical)
  • Copy vector string
Security & Privacy NEW

Bcrypt Hash Generator

Generate bcrypt hashes with configurable cost factors (4–14), or verify a plaintext string against an existing hash. All computation runs in your browser.

  • Cost factor 4–14
  • Hash + verify modes
  • Hash anatomy explainer
Security & Privacy NEW

Security Headers Grader

Grade any site's HTTP security headers from A+ to F. Tests HSTS, CSP, X-Frame-Options, Referrer-Policy, Permissions-Policy, COOP, and CORP with per-header recommendations.

  • A+–F grade with score
  • Per-header recommendations
  • All response headers dump
Developer Tools

Code Formatter

Beautify or minify JSON, HTML, JavaScript, CSS, SQL, XML, and PHP. Syntax errors highlighted.

  • 7 languages supported
  • Beautify & minify
  • Syntax validation
Developer Tools

Line Break Converter

Detect and convert line endings between LF (Unix), CRLF (Windows), and CR (legacy Mac).

  • Auto-detects mixed endings
  • LF / CRLF / CR output
  • Copy or download
Developer Tools

Secure .env Generator

Generate cryptographically secure secrets for .env files with configurable length and encoding.

  • CSPRNG secrets
  • Hex / Base64 / alphanumeric
  • Download .env
Developer Tools

Regex Tester

Test regular expressions against text with live match highlighting, group extraction, and flags.

  • Live match highlighting
  • Capture groups
  • Global / multiline flags
Developer Tools

Live HTML Viewer

Write HTML and preview it in Desktop and Mobile simultaneously with proportional scroll sync.

  • Dual-pane preview
  • Desktop + mobile
  • Scroll sync
Developer Tools NEW

Cron Expression Builder

Build and validate cron expressions visually. Presets, per-field editor, human-readable description, and next-10-runs preview.

  • Presets & field editor
  • Human-readable description
  • Next 10 run times
Developer Tools NEW

JSON Schema Validator

Validate JSON documents against a JSON Schema. Supports Draft-07 — not Draft-2020-12. Path-specific error messages, sample schemas, runs in browser.

  • Draft-07 (not 2020-12)
  • Path-specific errors
  • Sample schema & data
Developer Tools NEW

Text Diff Checker

Compare two text blocks line by line. Added, removed, and unchanged lines highlighted. Myers diff algorithm. Download .diff.

  • Myers diff algorithm
  • Ignore case / whitespace
  • Download .diff
Developer Tools NEW

Base64 Encoder / Decoder

Encode text or files to Base64, or decode Base64 back. Standard and URL-safe variants. File mode supports any file type.

  • Text & file modes
  • Standard & URL-safe
  • Copy data URI
Developer Tools NEW

URL Encoder / Decoder

Encode and decode URLs and URL components. Handles percent-encoding, query strings, full URLs, and includes a character reference table.

  • Component / Full URL / Query modes
  • Percent-encoding reference
  • Swap & copy
Developer Tools NEW

HTTP Status Reference

Searchable, filterable reference for all HTTP 1xx–5xx status codes with plain-English descriptions, RFC links, and use-case notes.

  • All 1xx–5xx codes
  • Search by code / name
  • RFC reference
Developer Tools NEW

Webhook Inspector

Paste a raw webhook payload to format, inspect and debug it. HMAC-SHA256 signature verifier, dot-path field extractor (e.g. data.user.email), and cURL builder.

  • HMAC-SHA256 signature verify
  • Extract any field (data.user.email)
  • Copy cURL command
Developer Tools NEW

UUID Generator

Generate UUID v4, v7, and v1-style identifiers in your browser. Bulk-generate up to 1000 UUIDs, copy or download. Includes structure diagrams.

  • v4 / v7 / v1-style
  • Bulk up to 1000
  • Copy or download .txt
Developer Tools NEW

IP Address Lookup

Look up geolocation, ISP, timezone, and network details for any IP address — or auto-detect your own public IP.

  • Auto-detect my IP
  • City / region / ASN
  • Open in Google Maps
Developer Tools NEW

Binary / Hex Converter

Convert numbers and text between binary, hex, decimal, and octal instantly. See binary digit breakdown per byte, ASCII table, and hex-to-text decoder.

  • Binary/Hex/Dec/Oct
  • See binary breakdown per byte
  • ASCII reference table
Developer Tools NEW

Robots.txt Generator

Build a valid robots.txt visually. Add user-agent rules, Disallow/Allow paths, crawl-delay, and sitemap URL. Includes AI-bot blocking preset.

  • Block AI crawlers preset
  • Sitemap support
  • Download robots.txt
Developer Tools NEW

.htaccess Builder

Generate Apache .htaccess directives with toggles. Force HTTPS, GZIP, browser caching, CORS, hotlink protection, custom 404, and security headers.

  • Force HTTPS + www
  • GZIP & caching
  • Security headers
Developer Tools NEW

JSONPath Tester

Test JSONPath expressions against any JSON document live. Supports wildcards, recursive descent, array slices, and filter expressions. Highlights matched paths.

  • Wildcard, filter & recursive queries
  • Live match highlighting
  • 3 sample datasets
Developer Tools NEW

XML Sitemap Generator

Build a valid XML sitemap from a list of URLs. Set priority and change-frequency globally or per URL, add a lastmod date, and download sitemap.xml.

  • URL validation
  • Homepage priority boost
  • Download sitemap.xml
Developer Tools NEW

Number Formatter

Format numbers for any locale and use case. 25+ locale presets, decimal / currency / percent / scientific / compact / accounting styles. Includes JS code snippet.

  • 25+ locale presets
  • 6 format styles
  • JS Intl.NumberFormat snippet
Developer Tools NEW

Schema Markup Generator

Generate JSON-LD structured data for Article, FAQ, Product, Local Business, Breadcrumb, How-To, Event, and Person schema types. Copy ready-to-paste markup.

  • 8 schema types
  • Copy with <script> tag
  • Google Rich Results link
Developer Tools NEW

Incident Response Writer

Generate a professional incident report from structured inputs. Fill in details, timeline, impact, and follow-up actions — export as Markdown instantly.

  • MTTD / MTTR auto-calculated
  • Event timeline builder
  • Markdown + .md download
Developer Tools NEW

RCA Generator

Build a structured Root Cause Analysis with 5-Why chain, contributing factors (People/Process/Tech/Environment), corrective actions, and lessons learned.

  • 5-Why analysis chain
  • P/P/T/E contributing factors
  • Blameless RCA report
Developer Tools NEW

Viewport & Screen Inspector

Instantly see your viewport size, DPR, screen resolution, orientation, touch points, CPU cores, and more — all detected automatically on page load.

  • Live resize updates
  • Device pixel ratio + physical px
  • Connection, memory & CPU info
Developer Tools NEW

Uptime SLA Calculator

Convert any SLA percentage into real downtime — per day, week, month, and year. Instant tier badge (two nines through five nines) and a reference table.

  • Day/week/month/year downtime
  • Tier badge (2 nines → 5 nines)
  • SLA reference table
Developer Tools NEW

API Rate Limit Calculator

Check whether your API traffic fits within a rate limit. Normalises any limit and traffic window to RPS and shows usage %, headroom, and an alert threshold.

  • Any time-window normalisation
  • Usage % + headroom
  • Alert at 80/85/90%
Developer Tools NEW

Website Speed Test

Test any URL for Core Web Vitals — LCP, FCP, CLS, TBT — with desktop and mobile Lighthouse scores plus actionable insights. Powered by Google PageSpeed Insights.

  • Desktop & mobile scores
  • LCP, FCP, CLS, TBT metrics
  • Actionable insights
Developer Tools NEW

Docker Image Size Estimator

Estimate your Docker image's compressed and uncompressed size. Pick a base image, add layers, and see a per-layer breakdown with a size-tier assessment.

  • 20+ base image presets
  • Per-layer breakdown
  • Compressed vs uncompressed
Developer Tools NEW

AI Token Counter

Count tokens for GPT-4o, Claude, Gemini, Llama, and Mistral using model-specific heuristics. See context window usage, tokens remaining, and estimated API cost.

  • 9 model presets
  • Context window bar
  • Cost estimate
Developer Tools NEW

LLM API Cost Estimator

Compare API costs for 17 LLMs side by side. Enter input/output tokens per call and daily volume for a monthly cost projection sorted cheapest-first.

  • 17 model pricing table
  • Monthly cost projection
  • Best-value callout
Developer Tools NEW

AI Prompt Length Checker

Check if your prompt fits within a model's context window. Set reserved output tokens and get a clear green/amber/red status with a stacked usage bar.

  • All major models
  • Reserved-output slider
  • Green/amber/red status
Developer Tools NEW

AI Model Context Reference

Searchable, sortable table of context windows, pricing, and notes for 35+ LLMs — GPT-4, Claude, Gemini, Llama, Mistral, Grok, and more. Data updated May 2025.

  • 35+ models
  • Sort by price or context
  • Provider filter

📊 Data & Files

5 tools
Content & Writing

Email Readability Analyser

Score your email copy for Flesch reading ease, spam triggers, and subject-line length.

  • Flesch reading score
  • Spam keyword check
  • Subject line analysis
Content & Writing NEW

Markdown Preview

Live split-pane Markdown editor with real-time preview. Supports GFM — tables, task lists, fenced code, strikethrough.

  • GitHub Flavored Markdown
  • Toggle dark/light preview
  • Copy HTML / Download .md
Content & Writing NEW

Markdown → LinkedIn Post

Convert Markdown to LinkedIn's vertical plain-text format. Unicode bold, bullets, hashtags.

  • Unicode bold headings
  • Emoji bullets
  • 3,000 char limit check
Content & Writing NEW

Citation Builder

Generate APA, MLA, Chicago, and IEEE citations for books, journals, websites, and videos.

  • APA / MLA / Chicago / IEEE
  • Copy HTML with italics
  • 5 source types
Content & Writing NEW

Table → WhatsApp Formatter

Paste a table from Excel or Google Sheets and get a clean text table for WhatsApp, Telegram, or Slack. Output styles: plain, markdown, monospaced, or bullets.

  • Plain / Markdown / Mono / Bullets
  • Excel & Google Sheets paste
  • Code-block wrapper
Content & Writing NEW

Email Warmup Plan Generator

Generate a day-by-day cold email warmup schedule. Ramp up sending volume safely to build domain reputation and avoid the spam folder.

  • Conservative / Moderate / Aggressive ramp
  • CSV export
  • Cold email best practices
Content & Writing NEW

Word Counter

Count words, characters, sentences, paragraphs, and reading time as you type. Keyword density, top-word frequency, and Flesch readability score.

  • Reading & speak time
  • Keyword density
  • Limit checker
Content & Writing NEW

Lorem Ipsum Generator

Generate classic Latin, developer slang, corporate buzzword, or emoji placeholder text by paragraphs, sentences, or word count. Copy HTML or plain text.

  • 4 text variants
  • Copy plain or HTML
  • Stats: words, chars
Content & Writing NEW
Aa

Text Case Converter

Convert text between 12 formats simultaneously — camelCase, PascalCase, snake_case, kebab-case, UPPER_SNAKE, Title Case, dot.case, and more. Hover to copy any.

  • 12 formats at once
  • Auto-detects separators
  • Hover-to-copy any result
Content & Writing NEW

Privacy Policy Generator

Generate a free, customisable privacy policy for your website. Covers GDPR, CCPA, cookies, Google Analytics, and third-party services. Download instantly.

  • GDPR + CCPA sections
  • Third-party service clauses
  • Download .txt
Content & Writing NEW

Terms & Conditions Generator

Generate free terms and conditions for your website, SaaS, or online store. Covers acceptable use, IP, liability, governing law, and more.

  • SaaS / e-commerce / blog types
  • Refund + subscription clauses
  • Download .txt
Content & Writing NEW

Google SERP Preview

Preview how your page looks in Google search results. Check title pixel length, meta description truncation, and URL breadcrumb — desktop and mobile views.

  • Live desktop + mobile preview
  • Title & description length check
  • Click-worthy snippet tips
Content & Writing NEW

Reading Time Estimator

Estimate reading time and speaking time for any text. Adjustable WPM slider, Flesch Reading Ease score, grade level, and readability improvement tips.

  • Adjustable reading speed
  • Flesch reading ease
  • Grade level & tips
Content & Writing NEW

Open Graph Tag Generator

Generate complete Open Graph and Twitter Card meta tags. Fill in title, description, image URL, page type, and copy the ready-to-paste HTML markup instantly.

  • OG + Twitter Card tags
  • Social card preview
  • Validation hints
Finance & Education NEW

Loan Payoff Visualizer

Calculate monthly payments, total interest, and amortization schedule for any loan. See the impact of extra payments.

  • Amortization chart
  • Extra payment savings
  • Full schedule table
Finance & Education NEW

Tax Quick-Slip 🇺🇸

Estimate US federal income tax, effective tax rate, and take-home pay using 2024 bracket data. US only — based on IRS brackets.

  • 2024 IRS tax brackets
  • Marginal vs effective rate
  • 401(k) pre-tax deductions
Finance & Education NEW

Grade-Curve Simulator 🎓

Apply square-root, flat boost, or custom curve to exam scores. See grade distribution and download results as CSV. For teachers and instructors.

  • 5 curve methods
  • Letter grade distribution
  • Download CSV
Finance & Education NEW

Timezone Converter

Convert any date and time across the world's timezones. Live world clock for 12 major cities. Uses Intl.DateTimeFormat.

  • Live world clock
  • Any-to-any conversion
  • Day/night indicators
Finance & Education NEW

Pomodoro Timer

Focused work timer with configurable 25/5/15-minute Pomodoro cycles. Session counter, audio chime, desktop notifications, and streak tracking.

  • Configurable durations
  • Desktop notifications
  • Session streak
Finance & Education NEW

Invoice Generator

Create professional invoices in your browser. Add line items, discounts, tax, and currencies. Download as PDF with one click — no account needed.

  • PDF download (print-to-PDF)
  • 8 currencies + tax + discount
  • Sample data loader
Finance & Education NEW

VAT / GST Calculator

Add or remove VAT and GST from any amount in one click. Choose Add Tax or Remove Tax mode, pick a preset rate, and get net, tax, and gross total instantly.

  • Add & remove (reverse) mode
  • 5 rate presets
  • Copy results to clipboard
Finance & Education NEW

Compound Interest Calculator

See how compound interest grows your savings or investment over time. Set compounding frequency, add regular contributions, and get a year-by-year growth chart.

  • Daily to annual compounding
  • Regular contribution support
  • Year-by-year chart
Finance & Education NEW

SaaS MRR / ARR Calculator

Calculate MRR, ARR, ARPU, and churn impact across multiple pricing tiers. Model up to 8 plans, set a monthly churn rate, and see net revenue after attrition.

  • Multi-tier plan builder
  • Churn impact & net MRR
  • ARPU & revenue mix table
Design

CSS Button Generator

Design production-ready CSS buttons with gradients, shadows, and hover effects. Live preview.

  • Gradient & shadow controls
  • Hover animation
  • Copy CSS
Design

Color Palette Picker

Generate shades, complementary, analogous, and triadic palettes from any hex colour.

  • Shades + tints
  • Complementary / triadic
  • HEX / RGB / HSL copy
Design NEW

Color Contrast Checker

Check foreground/background color pairs for WCAG 2.1 AA and AAA compliance. Get the contrast ratio with suggestions for fixing failures.

  • WCAG AA & AAA
  • Live preview
  • Auto-fix suggestions
Design

OpenGraph & Meta Inspector

Inspect any URL to see its live OG tags and social card previews — or build your own. Fetches real og:title, og:image, twitter:card, and all meta tags.

  • Inspect any live URL
  • 4 social card previews
  • Full raw tags table
Design NEW
Aa

Favicon Generator

Create a favicon from text or emoji. Choose background colour, shape, and font weight. Download as PNG at 16–512 px.

  • Text & emoji support
  • Rounded / circle shapes
  • Download all sizes
Design NEW

Image Format Converter

Convert images between JPG, PNG, WebP, BMP, and GIF. Resize, adjust quality, and download.

  • JPG / PNG / WebP / BMP
  • Quality slider
  • Download + Share
Design NEW

SVG Optimizer

Remove Inkscape/Illustrator metadata, empty groups, comments, and whitespace from SVG files. Preview before download.

  • 9 optimisation passes
  • Before/after size
  • Live preview
Design NEW

PDF Permission Unlocker

Remove owner-level printing, copying, and editing restrictions from PDFs without a password.

  • No password needed
  • Shows restriction flags
  • Download unlocked
Design NEW

Aspect Ratio Calculator

Calculate missing width or height from an aspect ratio. Scale proportionally, pick from presets (16:9, 4:3, 9:16, 1.91:1), and preview the result visually.

  • 16:9 / 4:3 / 9:16 presets
  • Scale slider
  • Megapixel count
Design NEW

CSS Gradient Generator

Build beautiful CSS gradients visually. Linear, radial, and conic types with unlimited colour stops, angle control, and position tuning. Copy the CSS or export.

  • Linear / Radial / Conic
  • Unlimited stops + presets
  • Copy background: CSS