New: Lottery Number Generator
Lottery Number Generator
Generate random lottery numbers for any game: pick the range, how many, and an optional bonus ball.
Updates
Everything we have shipped, newest first. New tools land regularly — check back or bookmark this page.
Powerball Number Generator & Mega Millions Number Generator
Powerball Number Generator
Generate random Powerball numbers: 5 from 1-69 plus a Powerball from 1-26.
Mega Millions Number Generator
Generate random Mega Millions numbers: 5 from 1-70 plus a Mega Ball from 1-24.
New: Scientific Calculator
Scientific Calculator
Trigonometry, logarithms, powers, roots and constants with memory.
Calculator & Fraction Calculator
Calculator
A simple online calculator with the four basic operations and percent.
Fraction Calculator
Add, subtract, multiply and divide fractions and simplify the result.
GPA Calculator & Discount Calculator
GPA Calculator
Calculate weighted or unweighted GPA from grades and credit hours.
Discount Calculator
Work out the sale price and how much you save from a percentage off.
New: Tip Calculator
Tip Calculator
Calculate a tip and split the bill between any number of people.
Sales Tax Calculator & Loan Calculator
Sales Tax Calculator
Add or remove sales tax / VAT from a price at any rate.
Loan Calculator
Monthly payment and total interest for a loan, with an amortization schedule.
New: Mortgage Calculator
Mortgage Calculator
Estimate a mortgage payment including taxes, insurance and PMI.
Compound Interest Calculator & BMI Calculator
Compound Interest Calculator
Project savings growth with compounding and regular contributions.
BMI Calculator
Calculate Body Mass Index in metric or imperial units with category.
Calorie Calculator & Age Calculator
Calorie Calculator
Estimate daily calories (TDEE) from the Mifflin-St Jeor equation.
Age Calculator
Find an exact age in years, months and days, and days until the next birthday.
New: Days Between Dates
Days Between Dates
Count the days, weeks and months between two dates.
Date Calculator & Days Until Date
Date Calculator
Add or subtract days, weeks, months or years from a date.
Days Until Date
Count down the days until a future date or event.
New: Hours Calculator
Hours Calculator
Work out the hours and minutes between two times, with a break deduction.
Countdown Timer & Online Stopwatch
Countdown Timer
A full-screen countdown timer with an alarm when it finishes.
Online Stopwatch
A precise online stopwatch with lap times.
Random Number Generator & Dice Roller
Random Number Generator
Generate random numbers in a range, with options for count and uniqueness.
Dice Roller
Roll one or more dice (D4 to D20 or custom sides).
New: Coin Flip
Coin Flip
Flip a virtual coin and track heads/tails streaks.
List Randomizer & SPF Record Generator
List Randomizer
Shuffle a list, pick winners or split it into random teams.
SPF Record Generator
Build a valid SPF (v=spf1) record from your senders, includes and policy.
New: DMARC Record Generator
DMARC Record Generator
Build a DMARC policy record with reporting and alignment options.
CSR / Certificate Decoder & HTML to Markdown
CSR / Certificate Decoder
Paste a CSR or certificate PEM and read its subject, SANs, key and validity.
HTML to Markdown
Convert HTML into clean Markdown, right in your browser.
IPv6 Subnet Calculator & MAC Address Lookup
IPv6 Subnet Calculator
Work out the network, address range and count for an IPv6 prefix.
MAC Address Lookup
Identify a device manufacturer from its MAC address and format it.
New: Email Health Check
Email Health Check
One domain, one click: MX, SPF, DMARC, DKIM, reverse DNS and blacklist checks together.
Percentage Calculator & JSON Minify
Percentage Calculator
Solve everyday percentage questions quickly.
JSON Minify
Strip whitespace from JSON to produce the smallest valid output.
New: JSON Escape / Unescape
JSON Escape / Unescape
Escape text into a JSON string literal, or unescape one back to raw text.
Sort Text Lines & Remove Duplicate Lines
Sort Text Lines
Sort lines alphabetically, numerically or reversed.
Remove Duplicate Lines
Strip duplicate lines from a block of text.
URL Parser & Roman Numeral Converter
URL Parser
Break a URL into scheme, host, path, query and fragment.
Roman Numeral Converter
Convert between Arabic numbers and Roman numerals.
New: MIME Type Lookup
MIME Type Lookup
Look up the MIME content type for any file extension and vice versa.
Color Contrast Checker & CSS Gradient Generator
Color Contrast Checker
Check colour contrast against WCAG AA and AAA thresholds.
CSS Gradient Generator
Design linear and radial CSS gradients and copy the code.
New: Box Shadow Generator
Box Shadow Generator
Build CSS box-shadow values with a live preview.
Unit Converter & Credit Card Validator
Unit Converter
Convert length, weight, temperature and data-size units.
Credit Card Validator
Check a card number with the Luhn algorithm and detect its network.
IBAN Validator & Email Normalizer
IBAN Validator
Validate an IBAN checksum and break out its country, bank and account parts.
Email Normalizer
Reduce an email address to its canonical form (Gmail dots, plus-tags).
New: HTTP Status Codes
HTTP Status Codes
A searchable reference of every HTTP status code and what it means.
Basic Auth Generator & IPv4 Range Expander
Basic Auth Generator
Build an HTTP Basic Authorization header from a username and password.
IPv4 Range Expander
Expand a CIDR block or start-end pair into its full IP range.
New: TOTP / 2FA Generator
TOTP / 2FA Generator
Generate time-based one-time passwords from a TOTP secret to verify 2FA.
RSA Key Pair Generator & cURL Command Builder
RSA Key Pair Generator
Generate an RSA public/private key pair in your browser via WebCrypto.
cURL Command Builder
Assemble a cURL command from method, URL, headers and body.
Docker Run to Compose & Cron Expression Generator
Docker Run to Compose
Convert a docker run command into a docker-compose.yml snippet.
Cron Expression Generator
Build a crontab expression from schedule pickers with a live preview.
New: JSON Diff
JSON Diff
Compare two JSON documents and highlight added, removed and changed keys.
SQL Formatter & XML Formatter
SQL Formatter
Beautify and indent SQL queries with keyword casing and dialect options.
XML Formatter
Pretty-print and indent XML, or minify it to a single line.
New: HTML Beautifier
HTML Beautifier
Format messy HTML for readability, or minify it.
CSS Beautifier & JavaScript Beautifier
CSS Beautifier
Pretty-print or minify CSS with consistent formatting.
JavaScript Beautifier
Format or minify JavaScript source code.
WiFi QR Code Generator & Image Format Converter
WiFi QR Code Generator
Make a QR code that joins a WiFi network from SSID and password.
Image Format Converter
Convert images between PNG, JPG and WebP in your browser.
New: Image Resizer
Image Resizer
Resize images to target dimensions in the browser.
Browser Privacy Check & What Is My IP
Browser Privacy Check
Our most in-depth privacy tool yet: it shows the complete fingerprint your browser exposes to every website — user agent and Client Hints, screen and hardware details, time zone, installed fonts, and the canvas, WebGL and audio fingerprints trackers use to recognise you without cookies. It even checks for WebRTC local-IP leaks and computes a combined fingerprint hash. Everything except your IP is gathered in your browser and never uploaded.
What Is My IP
Instantly see the public IP address every website sees for your connection, along with its type, reverse DNS name, and the network (ASN) and country it belongs to.
New: User Agent Parser
User Agent Parser
Paste any User-Agent string — or use your own — and break it down into browser, rendering engine, operating system, device type and architecture.
HTTP Request Headers & Light & Dark mode
HTTP Request Headers
See the exact HTTP headers your browser sends with every request, before any JavaScript runs, revealing what sites learn about your language, platform and preferences from the very first byte.
Light & Dark mode
A proper theme toggle now lives in the header. Pick light or dark to suit your eyes or your environment and the site remembers your choice, independent of your operating system setting.
Meta Tags Checker & Reverse DNS Lookup
Meta Tags Checker
Fetch any page and inspect its title, meta description, canonical, robots and Open Graph / Twitter Card tags, with a preview of how it would appear when shared on social media.
Reverse DNS Lookup
Turn an IPv4 or IPv6 address back into its PTR hostname — essential for diagnosing mail-server reputation and confirming forward-confirmed reverse DNS.
New: URL Redirect Checker
URL Redirect Checker
Trace a URL through its entire chain of 301, 302, 307 and 308 redirects to the final destination, with the status code at every hop.
IP Address Converter & QR Code Generator
IP Address Converter
Convert an IPv4 address between dotted, decimal, hexadecimal and binary forms, or expand and compress IPv6 addresses.
QR Code Generator
Turn any text or URL into a QR code with adjustable size and error-correction, then download it as a crisp PNG or scalable SVG — all in your browser.
New: Markdown to HTML
Markdown to HTML
Write Markdown and watch it render to clean, safe HTML in a live side-by-side preview, with the sanitized HTML source ready to copy.
JSON to CSV Converter & JSON to YAML Converter
JSON to CSV Converter
Convert JSON arrays of objects into CSV — and CSV straight back into JSON — with your choice of delimiter, all client-side so your data never leaves the page.
JSON to YAML Converter
Switch between JSON and YAML in either direction, handy for editing Kubernetes, Docker Compose and CI configuration files.
XML to JSON Converter & Image to Base64
XML to JSON Converter
Convert XML to JSON and back, preserving attributes and repeated elements, right in your browser.
Image to Base64
Encode an image into a Base64 data URI — with ready-to-paste HTML and CSS snippets — or decode one back into a downloadable image, without ever uploading the file.
New: AES Encrypt / Decrypt
AES Encrypt / Decrypt
Encrypt or decrypt text with AES-256-GCM and a passphrase using the browser Web Crypto API, so your secrets are processed entirely on your own device.
Chmod Calculator & Timezone Converter
Chmod Calculator
Convert Unix file permissions between the checkbox grid, the symbolic string (rwxr-xr-x) and the octal number (755), with the matching chmod command.
Timezone Converter
Convert a date and time between world time zones with automatic daylight-saving handling, plus a live world clock for that instant.
New: Text Compare
Text Compare
Compare two blocks of text side by side with word-level highlighting and per-line numbers, correctly handling moved and reflowed passages.
Word Counter & Slugify
Word Counter
Count words, characters, sentences and paragraphs, with an estimated reading time, as you type.
Slugify
Turn any title or heading into a clean, lowercase, URL-friendly slug in one click.
Lorem Ipsum Generator & Case Converter
Lorem Ipsum Generator
Generate placeholder paragraphs, sentences or words to fill out designs and mock-ups.
Case Converter
Convert text between UPPERCASE, lowercase, Title Case, camelCase, snake_case and kebab-case instantly.
New: Color Converter
Color Converter
Convert colours between HEX, RGB and HSL with a live preview swatch.
HTML Entity Encoder & Number Base Converter
HTML Entity Encoder
Encode or decode HTML entities so special characters display correctly and safely in markup.
Number Base Converter
Convert numbers between binary, octal, decimal and hexadecimal.
New: JWT Decoder
JWT Decoder
Decode a JSON Web Token to inspect its header and payload, and verify HMAC (HS256/384/512) signatures with a secret.
HMAC Generator & Bcrypt Hash & Verify
HMAC Generator
Compute an HMAC signature (SHA-256/512, SHA-1 or MD5) from a key and message.
Bcrypt Hash & Verify
Generate a bcrypt password hash or check a password against an existing hash, the same way a login system does.
Password Strength & Cron Explainer
Password Strength
Estimate how strong a password is by its entropy and see roughly how long it would take to crack.
Cron Explainer
Translate a cron expression into plain English and list its upcoming run times.
New: Regex Tester
Regex Tester
Test a regular expression against sample text, see every match and capture group, or run a find-and-replace.
UUID Generator & Password Generator
UUID Generator
Generate UUID v4 (random) or v7 (time-ordered) identifiers in bulk.
Password Generator
Create strong random passwords with adjustable length and character rules.
New: Hash Generator
Hash Generator
Compute MD5, SHA-1, the SHA-2 and SHA-3 families, RIPEMD-160 and CRC32 checksums of any text.
Epoch Converter & Base64 Encode / Decode
Epoch Converter
Convert between Unix timestamps and human-readable dates in both directions.
Base64 Encode / Decode
Encode text to Base64 or decode it back, quickly and safely.
URL Encode / Decode & JSON Formatter
URL Encode / Decode
Percent-encode or decode URLs and query-string values.
JSON Formatter
Pretty-print, validate or minify JSON, with clear error messages when it is malformed.
New: Subnet Calculator
Subnet Calculator
Work out network and broadcast addresses, masks, host ranges and counts from any IPv4 CIDR block.
Punycode / IDN Converter & SSL Certificate Checker
Punycode / IDN Converter
Convert internationalised domain names between Unicode and their punycode (xn--) representation.
SSL Certificate Checker
Inspect a site TLS certificate: issuer, validity dates, key type and size, SANs, fingerprint and whether the chain is trusted.
New: HTTP Headers Viewer
HTTP Headers Viewer
View any URL response headers and follow its redirect chain.
Security Headers & Port Checker
Security Headers
Grade a site on HSTS, Content-Security-Policy, X-Frame-Options and other important security headers.
Port Checker
Test whether common or custom TCP ports are open on a host.
IP Info & SPF Checker
IP Info
Look up the reverse DNS, ASN, network and country for any public IP address.
SPF Checker
Fetch a domain SPF record and recursively count its DNS lookups against the 10-lookup limit, showing the full include chain.
New: DMARC Checker
DMARC Checker
Read and explain a domain DMARC policy, including alignment, percentage and reporting settings.
DKIM Checker & Email Verifier
DKIM Checker
Look up a DKIM public key by selector and report its exact key size.
Email Verifier
Validate an email address by syntax, domain MX records, and role or disposable detection, with a live mailbox probe.
New: Email Header Analyzer
Email Header Analyzer
Paste raw email headers to trace the delivery path and spot delays hop by hop.
DNS Propagation & MX Lookup
DNS Propagation
Check a DNS record across 14 public resolvers in the US and around the world to see how far a change has propagated.
MX Lookup
List a domain mail servers in priority order to confirm where its email is delivered.
Blacklist Check & WHOIS Lookup
Blacklist Check
Check whether an IP address appears on the major DNS blacklists (RBLs) used to fight spam.
WHOIS Lookup
Look up a domain registration, registrar, key dates and nameservers with a live WHOIS query.
Core Web Utilities is live
Core Web Utilities is officially live — a fast, free, no-nonsense collection of web tools with no ads, no sign-up and nothing you enter stored. We are starting with the essentials and adding more every few days. Here is where it all began:
DNS Lookup
The tool it all started with: a dig-style DNS lookup for A, AAAA, MX, TXT, NS, SOA, SRV, CAA and PTR records, complete with a subdomain sweep.