How the word counter works

This tool counts words by splitting your text on whitespace, so contractions and hyphenated words (like "well-known") count as a single word, matching how most word processors count. Characters are counted both with and without spaces so you can match requirements for essays, captions, or forms with strict character limits. Sentences are estimated by counting terminating punctuation (. ! ?), and paragraphs are estimated by counting line breaks — both are close approximations rather than exact grammatical parses, since true sentence detection requires understanding abbreviations and context.

Common use cases

• Checking an essay or article against a required word count before submitting it
• Trimming a social media caption or ad headline down to a character limit
• Estimating how long a speech or presentation script will take to read aloud
• Comparing draft lengths when editing down a long piece of writing
• Checking meta description or title length for SEO purposes

Step-by-step guide

1. Click into the text box and type, or paste in existing text with Ctrl/Cmd + V.
2. Watch the counts on the right update instantly as you edit — there's no "Calculate" button to press.
3. Use the reading-time estimate (based on an average of 200 words per minute) to gauge how long a reader will spend on your text.
4. Use the speaking-time estimate (based on roughly 130 words per minute) if you're timing a speech or video script.
5. Copy your finished text back out with Ctrl/Cmd + A then Ctrl/Cmd + C.

Frequently asked questions

How the password generator works

This generator builds a password by randomly selecting characters from the character sets you enable, using your browser's crypto.getRandomValues() API where available for cryptographically strong randomness rather than a predictable pseudo-random function. The strength meter below the result estimates strength from a combination of length and character-set variety — longer passwords that mix character types score higher.

Common use cases

• Creating a new account password that's hard to guess or brute-force
• Generating a unique password for every site so a single leak doesn't compromise other accounts
• Creating a temporary password to share with a teammate before they set their own
• Generating a passphrase-style secret for Wi-Fi networks or shared devices

Step-by-step guide

1. Drag the length slider to your desired password length — 16+ characters is a good default for most accounts.
2. Tick the character types you want included; leaving all four checked gives the strongest mix.
3. Optionally exclude ambiguous characters like l, 1, O and 0 if you'll be reading the password aloud or typing it on a device with a small screen.
4. Click "Generate password" — click it again any time for a new one.
5. Click "Copy to clipboard" and paste the password straight into your account's password field.

Frequently asked questions

How BMI is calculated

Body Mass Index is calculated as weight in kilograms divided by height in metres squared (BMI = kg / m²). For imperial units, the equivalent formula is weight in pounds multiplied by 703, divided by height in inches squared. BMI is a simple screening measure, not a diagnostic tool — it doesn't distinguish between muscle and fat, so very muscular people can show a higher-than-expected BMI despite low body fat, and it doesn't account for age, sex, or body composition directly.

Common use cases

• Getting a quick, general sense of whether your weight falls in a typical healthy range for your height
• Tracking BMI over time alongside other health metrics as part of a fitness routine
• Preparing figures ahead of a doctor's appointment or health check-up
• Understanding the standard weight categories used in general health guidance

Step-by-step guide

1. Choose metric or imperial units depending on what you know your height and weight in.
2. Enter your height (in centimetres, or feet and inches) and your current weight.
3. Click "Calculate BMI" to see your result and which of the four general categories it falls into.
4. Compare your number against the reference table to the right of the calculator.

Frequently asked questions

How the unit converter works

For length and weight, this tool converts your input to a common base unit (metres for length, kilograms for weight) and then converts that base value into your chosen output unit, using standard conversion factors. Temperature uses the correct non-linear formulas for Celsius, Fahrenheit and Kelvin rather than a simple multiplier, since temperature scales have different zero points.

Common use cases

• Converting a recipe's weight measurements between grams and ounces
• Checking a shipping package's dimensions in both centimetres and inches
• Converting a weather forecast's temperature between Celsius and Fahrenheit while travelling
• Converting distances between kilometres and miles for running or driving

Step-by-step guide

1. Choose a category: Length, Weight, or Temperature.
2. Enter a value and choose the unit you're converting from.
3. Choose the unit you want to convert to — the result updates instantly.
4. Use the "Swap units" button to quickly reverse the conversion direction.

Frequently asked questions

How the case converter works

Each button applies a different transformation to your text using JavaScript's built-in string methods, plus custom logic for Title Case (capitalising the first letter of each major word) and Sentence case (capitalising the first letter after each terminating punctuation mark). The original text you typed stays untouched in the input box, so you can try multiple styles without retyping.

Common use cases

• Fixing text that was accidentally typed with Caps Lock left on
• Formatting a blog post title into consistent Title Case
• Cleaning up pasted text from a PDF or email that came through in all caps
• Creating a playful alternating-case caption for social media

Step-by-step guide

1. Paste or type your text into the top box.
2. Click the case style you want — the converted result appears immediately below.
3. Click "Copy result" to copy the converted text to your clipboard.

Frequently asked questions

How the diff checker works

This tool splits both texts into words and runs a longest-common-subsequence comparison to work out the smallest set of insertions and deletions that turns the original text into the changed text. Words that appear only in the original are shown struck through in red; words that only appear in the changed version are highlighted in green. Words present in both are shown as plain text.

Common use cases

• Reviewing an editor's changes to an article or essay draft
• Checking exactly what changed between two versions of a contract or policy
• Comparing AI-generated rewrites against your original wording
• Spotting subtle edits in pasted text that look identical at a glance

Step-by-step guide

1. Paste your original text into the left box and the revised version into the right box.
2. Click "Compare texts".
3. Read the highlighted result: red strikethrough words were removed, green words were added.

How the generator works

The generator draws from a fixed pool of classic Lorem Ipsum words — the scrambled Latin passage that's been the default placeholder text in publishing and design since the 1500s — and assembles them into sentences and paragraphs of randomized, natural-looking length. Because the words are meaningless Latin fragments, they don't distract a reviewer's eye toward the words themselves, letting you judge layout, spacing, and typography instead.

Common use cases

• Filling a website or app mockup with realistic-looking body text before real copy is ready
• Testing how a design handles long headlines, short paragraphs, or dense blocks of text
• Populating a CMS template during development
• Demoing a print layout without waiting on final copywriting

Step-by-step guide

1. Choose how much text you want and whether to count it in paragraphs, sentences, or words.
2. Leave "Start with Lorem ipsum dolor sit amet…" checked if you want the traditional opening line.
3. Click "Generate text", then copy the result into your mockup or document.

How each calculation works

"X% of Y" multiplies Y by X/100. "X is what % of Y" divides X by Y and multiplies by 100. The increase/decrease calculator subtracts the starting value from the ending value, divides by the starting value, and multiplies by 100 — a positive result means an increase, a negative result means a decrease.

Common use cases

• Working out a discount amount or a tip on a bill
• Calculating what portion of a budget or target a number represents
• Finding how much a price, salary, or metric has grown or shrunk between two periods
• Checking exam or quiz scores as a percentage

How this converter works

Every currency in the table is stored as a rate relative to one US dollar. To convert, your amount is first converted into US dollars using the "from" currency's rate, then converted from US dollars into the "to" currency. Because the rate table is fixed at build time rather than fetched live, results are approximate reference values, not real-time market rates.

Common use cases

• Getting a rough sense of a price while browsing a foreign online store
• Roughly budgeting for a trip in a destination currency
• Sanity-checking a currency figure in a report or spreadsheet

How image compression works here

When you choose a file, it's drawn onto an in-memory HTML canvas, then re-exported as a JPEG using the browser's built-in canvas.toBlob() quality setting. Lowering the quality slider increases the amount of lossy compression applied, trading a small amount of visual detail for a smaller file size. Because everything happens through browser APIs, the original image file is never uploaded anywhere.

Common use cases

• Shrinking a photo before attaching it to an email with a size limit
• Reducing an image's file size before uploading it to a website for faster page loads
• Preparing lighter images for a slide deck or document

Step-by-step guide

1. Click "Choose an image" and select a JPEG or PNG file from your device.
2. Drag the quality slider — lower values produce smaller files but more visible compression artifacts.
3. Compare the original and compressed previews and file sizes side by side.
4. Click "Download compressed image" to save the result.

How PDF merging works

Each selected PDF is read into memory and its pages are copied, in order, into one new PDF document, using the open-source pdf-lib library running entirely in your browser. Files are combined in the order they're listed below the file picker — add files one at a time if you need a specific order, since browser file pickers don't always preserve your selection order.

Common use cases

• Combining several scanned pages into one PDF to send as a single attachment
• Merging a cover letter and a résumé into one file for a job application
• Assembling multiple chapters or reports into a single combined document

Step-by-step guide

1. Click "Choose PDF files" and select the PDFs you want to combine (hold Ctrl/Cmd to multi-select, or add files one at a time).
2. Check the file list to confirm the order — remove and re-add files if you need to reorder them.
3. Click "Merge PDFs".
4. Click "Download merged PDF" once merging finishes.

How this formatter works

"Format / Validate" runs your input through the browser's built-in JSON.parse, which throws a descriptive error if the JSON is malformed, then re-serializes it with two-space indentation using JSON.stringify. "Minify" does the same parse step but serializes without any whitespace, producing the smallest possible valid JSON string.

Common use cases

• Making a minified API response readable for debugging
• Checking that hand-written JSON (for a config file, for example) is syntactically valid before using it
• Shrinking a JSON payload's size before sending it somewhere with a size limit