Free Online Tools — Buff Follow - Bufffollow Nhanh, Uy Tín, Giá Rẻ Nhất
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Free Online Tools
Utilities that run right in your browser — free, no sign-up, your data is never stored.
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Text
36
Word Counter
Count words, characters, lines, sentences, paragraphs and estimate reading time for your text.
Case Converter
Convert text to UPPERCASE, lowercase, Title Case, camelCase, snake_case and more.
Text to Slug
Turn titles into SEO-friendly URL slugs: strip accents, lowercase, replace spaces.
Lorem Ipsum Generator
Generate Lorem Ipsum placeholder text by paragraphs, sentences, words or bytes for design and mockups.
Text Diff Checker
Compare two texts, highlighting added and removed parts and computing similarity.
Article Rewriter
Rewrite English articles by swapping in basic synonyms, running in your browser.
Text to Hashtags
Extract hashtags from text by word frequency, with adjustable count and minimum length.
Hashtag Generator
Generate hashtag sets by topic and category like travel, food, fitness for social media.
Backwards Text Generator
Reverse the whole text or reverse each word while keeping word order.
Remove Line Breaks
Remove line breaks, merge text into one paragraph or just strip extra blank lines.
Remove Vietnamese Accents
Convert accented Vietnamese text to unaccented text instantly in your browser.
Random Sentence Generator
Generate random English sentences for testing, placeholders and content ideas.
Duplicate Line Remover
Remove duplicate lines with options to ignore case, trim spaces and sort.
Text Replacer
Bulk find and replace in text, with case sensitivity and regex support.
Text Cleaner
Clean text: collapse spaces, remove blank lines, special characters and normalize formatting.
Comma Separator
Convert multi-line lists to comma-separated strings and back, with optional quotes.
Small Text Generator
Create small Unicode text: small caps, superscript and subscript for bios and social media.
Word Combiner
Combine two word lists into every combination, great for SEO keywords and domain names.
Text to Speech
Read text aloud right in your browser with adjustable voice, rate and pitch.
Email Extractor
Extract all email addresses from any text, one per line, with duplicates removed.
URL Extractor
Extract every URL link from text or HTML, one per line, duplicates removed.
List Randomizer
Randomly shuffle the order of lines, great for draws and random picking.
List Alphabetizer
Sort lines alphabetically A to Z or Z to A, with Vietnamese support.
Reverse List
Reverse the order of lines so the last becomes first and vice versa.
Reverse Words
Reverse the order of words in a sentence while keeping each word intact.
Emoji Remover
Strip all emoji and emoticons from text, keeping only the plain characters.
Upside Down Text
Create upside-down Unicode text for Facebook, Instagram and TikTok bios.
Cursive Text Generator
Generate fancy cursive script text with Unicode for Instagram and Facebook bios.
Old English Text
Create Old English / Gothic Fraktur Unicode text for logos, tattoos and bios.
Palindrome Checker
Check whether a word or phrase is a palindrome, with optional case sensitivity.
Text Size Calculator
Calculate text size in bytes (UTF-8), KB, plus character, word, line and sentence counts.
HTML Tags Remover
Strip all HTML tags to plain text, with an option to keep line breaks.
Markdown to HTML
Convert Markdown to HTML with live preview, supporting headings, lists, links and tables.
BBCode to HTML
Convert forum BBCode to HTML: bold, italic, url, img, quote, code, list and color.
Text Converter
Convert between Text, Hex, Binary and Decimal (ASCII) in real time.
Punycode Converter
Convert Unicode (IDN) domains to Punycode (xn--) and back per RFC 3492.
Developer
30
JSON Formatter
Beautify, minify and validate JSON syntax.
Base64 Encode/Decode
Encode and decode Base64 strings (full Unicode support).
URL Encode/Decode
Encode and decode URLs (percent-encoding).
JSON Escape / Unescape
Add or remove escape characters from JSON strings for safe embedding.
JSON ↔ XML Converter
Two-way conversion between JSON and XML with readable formatting.
JSON Schema Generator
Generate a JSON Schema (draft-07) automatically from sample JSON data.
Base64 to Image
Convert a Base64 string or Data URI to an image, preview and download.
URL Parser
Break down and inspect URL components: host, path, query and hash.
JWT Decoder
Decode and inspect a JSON Web Token: header, payload and signature.
HMAC Generator
Generate HMAC (SHA-256/1/512) from a message and secret key.
Hash Generator
Generate MD5, SHA-1/224/256/384/512, SHA-3, RIPEMD-160 and CRC32 from text.
UUID Generator
Generate unique identifiers UUID v1 and v4, in bulk up to 100 at once.
HTML Encoder / Decoder
Convert special characters to HTML entities and back for safe display.
Unix Timestamp Converter
Convert Unix timestamp to date-time and back, in UTC and local time.
Number Base Converter
Convert numbers between binary, octal, decimal and hexadecimal.
CSS Beautifier
Format and indent CSS code so it is clean, readable and easy to maintain.
CSS Minifier
Minify CSS by stripping whitespace and comments to reduce file size.
HTML Beautifier
Format and indent HTML code so it is clean, readable and easy to edit.
HTML Minifier
Minify HTML by removing extra whitespace and comments to reduce size.
JS Beautifier
Format, indent and line-break JavaScript code for readability.
JS Minifier
Minify JavaScript with Terser to reduce file size.
JS Obfuscator
Obfuscate JavaScript (Base64/CharCode) to make it hard to read or copy.
XML Beautifier
Format and indent XML code for readability and structure checking.
XML Minifier
Minify XML by removing whitespace and comments between tags.
Random JSON Generator
Generate sample JSON data (users, products) to test APIs and mock data.
Random XML Generator
Generate random sample XML data to test and mock applications.
SQL Formatter
Format and prettify SQL queries across dialects with proper indentation.
Bulk URL Opener
Open many URLs at once in new browser tabs.
URL Rewriting Tool
Convert query-string URLs into clean SEO-friendly URLs.
.htaccess Redirect Generator
Generate 301/302 redirect rules for Apache .htaccess files.
Image & Color
18
Color Converter
Convert colors between HEX, RGB and HSL formats.
Color Picker
Pick colors visually and copy HEX, RGB, HSL codes.
Gradient Generator
Build linear and radial CSS gradients visually.
Box Shadow Generator
Create CSS box-shadow effects with sliders and live preview.
Image Compressor
Compress images in your browser without uploading.
Image Resizer
Resize images quickly while keeping aspect ratio.
Image Converter
Convert images between PNG, JPG, WEBP, BMP, ICO.
Image to Base64
Convert images into Base64 Data URI strings to embed.
Favicon Generator
Generate multi-size favicons from an image with embed code.
SVG to PNG
Convert SVG code to PNG with selectable resolution.
SVG to JPG
Convert SVG code to white-background JPG with quality control.
EXIF Reader
Read image EXIF metadata: camera, ISO, aperture, GPS.
HEIC Converter
Convert iPhone HEIC/HEIF photos to JPG or PNG.
Image to Text (OCR)
Extract text from images via OCR, Vietnamese and English.
QR Code Reader
Read and decode QR code content from an uploaded image.
Barcode Reader
Read 1D/2D barcodes like EAN, UPC, Code 128, QR from images.
Meme Generator
Create memes with top/bottom Impact captions and download.
Signature Pad
Draw a handwritten signature and download a transparent PNG.
Converters
16
Length Converter
Quickly convert between meter, km, cm, mm, mile, yard, foot, inch.
Weight Converter
Convert kg, gram, mg, tonne, pound, ounce, stone.
Temperature Converter
Convert temperature between Celsius, Fahrenheit and Kelvin.
Area Converter
Convert m², km², hectare, acre, square foot, square mile.
Volume Converter
Convert liter, ml, m³, gallon, quart, cup, fl oz, tbsp, tsp.
Speed Converter
Convert m/s, km/h, mph, knot, ft/s.
Time Converter
Convert second, minute, hour, day, week, month, year.
Pressure Converter
Convert Pascal, kPa, bar, psi, atm, mmHg, torr.
Power Converter
Convert Watt, kW, MW, horsepower (hp), BTU/h.
Torque Converter
Convert N·m, kgf·m, lbf·ft, lbf·in.
Data Storage Converter
Convert bit, Byte, KB, MB, GB, TB, PB (1000/1024 standard).
Voltage Converter
Convert Volt, millivolt, microvolt, kilovolt, megavolt.
Fuel Economy Converter
Convert km/L, MPG (US/UK), L/100km, gallon/100mi.
Roman Numeral Converter
Convert numbers to Roman numerals and back (1–3999).
Number to Words
Convert numbers into Vietnamese and English words (amounts).
Morse Code Converter
Convert text to Morse code and back, with audio playback.
Calculators
12
AdSense Revenue Calculator
Estimate daily, monthly and yearly Google AdSense revenue from page views, CTR and CPC.
Age Calculator
Calculate exact age in years, months, days, total days lived and days to next birthday.
Average Calculator
Calculate the mean, median, sum, minimum and maximum of a set of numbers.
Percentage Calculator
Find X% of Y, what percent X is of Y, and the percent increase/decrease between two numbers.
Discount Calculator
Calculate the final price and the amount saved when applying a percentage discount.
Probability Calculator
Compute single-event probability and the combined probability of two independent events.
Sales Tax Calculator
Calculate tax amount and after-tax total, or extract tax from a tax-inclusive price.
Reading Time Calculator
Estimate reading and speaking time of a text based on word count and custom reading speed.
Uptime / Downtime Calculator
Calculate allowed downtime for an SLA uptime level per day, week, month and year.
Random Number Generator
Generate random numbers within a chosen range, multiple at once, with a no-duplicate option.
Calorie Calculator
Plan daily calories and macros to reach your weight loss or weight gain goal.
TDEE Calculator
Calculate BMR and TDEE from weight, height, age, gender and activity level.
Generators & Marketing
17
Meta Tags Generator
Generate SEO-friendly meta tags (title, description, keywords, author) for your website.
Open Graph Generator
Create Open Graph tags to optimize how your link looks when shared on Facebook and Zalo.
Twitter Card Generator
Generate Twitter Card tags so your posts look great when shared on Twitter (X).
Robots.txt Generator
Create a robots.txt file to control how search engine bots crawl your website.
FAQ Schema Generator
Generate schema.org FAQ JSON-LD markup for Google rich snippets.
UTM Builder
Build UTM tracking links for marketing campaigns, compatible with Google Analytics.
QR Code Generator
Generate QR codes for URLs, text, email, phone and WiFi, download as PNG.
Barcode Generator
Generate CODE128, EAN-13, UPC and CODE39 barcodes for products, download as SVG.
Credit Card Generator
Generate Luhn-valid fake credit card numbers (Visa, MasterCard, Amex) for software testing.
Fake Name Generator
Generate random fake identities (name, gender, email, phone, date of birth) for testing.
Fake Address Generator
Generate random fake Vietnamese and US addresses for testing forms and sample data.
WhatsApp Link Generator
Create WhatsApp wa.me chat links with phone number and a prefilled message.
Mailto Link Generator
Generate mailto links with To, CC, BCC, subject and a prefilled body.
PayPal.me Link Generator
Create PayPal.me payment links with username, amount and currency.
YouTube Timestamp Link
Create a YouTube link that starts at a specific timestamp (h:m:s).
YouTube Thumbnail Downloader
Download HD thumbnail images from any YouTube video.
Twitter Character Counter
Count characters, words and remaining characters for Twitter (X) posts up to the 280 limit.
Security
4
Password Generator
Generate strong random passwords with custom length and character sets, fully in your browser.
Password Strength Checker
Score your password security out of 100 and get instant suggestions to make it stronger.
Bcrypt Generator & Verifier
Generate bcrypt hashes with custom cost and verify a password against a hash, right in your browser.
Text Encryption Tool
Encrypt and decrypt text with a secret key (XOR + Base64) in your browser, no data sent anywhere.
Video Downloader
23
YouTube Video Downloader
Download YouTube videos in high quality — free, no login or software needed.
TikTok Video Downloader
Download TikTok videos in high quality — free, no login or software needed.
Facebook Video Downloader
Download Facebook videos in high quality — free, no login or software needed.
Instagram Video Downloader
Download Instagram videos in high quality — free, no login or software needed.
X (Twitter) Video Downloader
Download X (Twitter) videos in high quality — free, no login or software needed.
Pinterest Video Downloader
Download Pinterest videos in high quality — free, no login or software needed.
Reddit Video Downloader
Download Reddit videos in high quality — free, no login or software needed.
Vimeo Video Downloader
Download Vimeo videos in high quality — free, no login or software needed.
Dailymotion Video Downloader
Download Dailymotion videos in high quality — free, no login or software needed.
SoundCloud Video Downloader
Download SoundCloud videos in high quality — free, no login or software needed.
Twitch Video Downloader
Download Twitch videos in high quality — free, no login or software needed.
Tumblr Video Downloader
Download Tumblr videos in high quality — free, no login or software needed.
Bilibili Video Downloader
Download Bilibili videos in high quality — free, no login or software needed.
Bluesky Video Downloader
Download Bluesky videos in high quality — free, no login or software needed.
Snapchat Video Downloader
Download Snapchat videos in high quality — free, no login or software needed.
Streamable Video Downloader
Download Streamable videos in high quality — free, no login or software needed.
VK Video Downloader
Download VK videos in high quality — free, no login or software needed.
OK.ru Video Downloader
Download OK.ru videos in high quality — free, no login or software needed.
RuTube Video Downloader
Download RuTube videos in high quality — free, no login or software needed.
Loom Video Downloader
Download Loom videos in high quality — free, no login or software needed.
Newgrounds Video Downloader
Download Newgrounds videos in high quality — free, no login or software needed.
Xiaohongshu (RED) Video Downloader
Download Xiaohongshu (RED) videos in high quality — free, no login or software needed.
Universal Video Downloader
Download videos from most websites: auto-extracts the video link and lets you save it.