Guides & Tutorials
Learn how every tool works
74 in-depth, keyword-targeted guides — the formulas, step-by-step methods and worked examples behind every utility, from unscrambling letters to calculating compound interest.
Showing 74 of 74 guides.
Guides on unscrambling letters, finding anagrams, counting words and characters, and cleaning up text — everything you need to win word games and format copy.
- How to Unscramble Letters Into WordsLearn how word unscramblers work, how to approach difficult letter combinations, and how to get better results when solving word puzzles.Read guide Updated Sep 10, 2026
- How to Find Anagrams of Any WordUnderstand what a true anagram is, how anagram solvers work, and practical techniques for spotting anagrams in puzzles and games.Read guide Updated Sep 8, 2026
- How to Count Words, Characters and Reading Time AccuratelyLearn what word and character counters measure, why limits exist, and how to use a counter to hit essay, post and metadata targets.Read guide Updated Sep 8, 2026
- How to Find Words by Pattern, Length and LettersDiscover how word finders filter a dictionary by starting, ending and contained letters, and how to use patterns for games and writing.Read guide Updated Sep 8, 2026
- How to Use a Random Word Generator for Games, Writing and BrainstormingLearn how random word generators work and creative, practical ways to use them for games, naming, vocabulary and writing prompts.Read guide Updated Sep 8, 2026
- How to Count Characters (With and Without Spaces)Understand the difference between character counts with and without spaces, and where exact character limits matter online.Read guide Updated Sep 8, 2026
- How to Convert Text Between Cases (UPPER, lower, Title, camelCase and More)Learn every text case format, when to use each, and how a case converter saves time on formatting code, headings and data.Read guide Updated Sep 8, 2026
- How to Clean Up Messy Text (Spaces, Line Breaks and Whitespace)See what text cleaning fixes, why pasted text gets messy, and how to normalise whitespace in one pass.Read guide Updated Sep 8, 2026
- How to Remove Duplicate Lines From a ListLearn why duplicate lines creep into lists, how deduplication works, and how to clean CSVs, keyword lists and logs.Read guide Updated Sep 8, 2026
- How to Sort Lines Alphabetically, Numerically and by LengthUnderstand the different ways to sort a list of lines and how to choose the right mode for names, numbers and data.Read guide Updated Sep 8, 2026
- How to Reverse Text — Characters, Words and LinesLearn the different ways to reverse text and where each is genuinely useful, from coding to puzzles to formatting.Read guide Updated Sep 8, 2026
- How to Find and Replace Text (Including With Regex)Master find-and-replace from simple swaps to regex patterns, and learn safe habits that prevent costly mistakes.Read guide Updated Sep 8, 2026
- How to Compare Two Texts and Spot Every DifferenceLearn how text diff tools highlight additions and removals, and how to use them for editing, version control and review.Read guide Updated Sep 8, 2026
- How to Create Clean, SEO-Friendly URL SlugsLearn what a slug is, the rules for good slugs, and how a slug generator keeps your URLs clean and consistent.Read guide Updated Sep 8, 2026
- How to Convert Text Into a List (Comma, Line, or Custom Delimited)See how to split a block of text into a structured list and format it for spreadsheets, code and display.Read guide Updated Sep 8, 2026
Guides on percentages, discounts, tax, tips, loans, mortgages, compound interest, dates and statistics — the maths behind everyday numbers, explained simply.
- How Percentages Work (and How to Calculate Them)Understand what a percentage is, the three core percentage calculations, and how to avoid common percentage mistakes.Read guide Updated Sep 10, 2026
- How to Calculate Percentage Change (Increase and Decrease)Learn the percentage-change formula, the difference between absolute and relative change, and common pitfalls.Read guide Updated Sep 8, 2026
- How to Calculate a Discount and the Final Sale PriceLearn the discount formula, how to work backwards from a sale price, and how to spot misleading discounts.Read guide Updated Sep 8, 2026
- How to Add or Remove Sales Tax, VAT and GSTUnderstand tax-inclusive vs. tax-exclusive pricing and how to add or extract tax at any rate.Read guide Updated Sep 8, 2026
- How to Calculate a Tip and Split the BillLearn tipping etiquette, the tip formula, and how to split a bill fairly across a group.Read guide Updated Sep 8, 2026
- How to Split a Bill Fairly Across a GroupLearn even and per-item bill splitting, how to handle tip and tax, and how to keep group payments fair.Read guide Updated Sep 8, 2026
- How to Simplify and Solve RatiosUnderstand what a ratio is, how to simplify one, and how to solve a proportion for a missing value.Read guide Updated Sep 8, 2026
- How to Add, Subtract, Multiply and Divide FractionsLearn the rules for fraction arithmetic, how to simplify results, and how to convert between fractions, mixed numbers and decimals.Read guide Updated Sep 8, 2026
- How to Calculate Mean, Median, Mode and RangeUnderstand the four common summary statistics, when each is meaningful, and how to interpret them.Read guide Updated Sep 8, 2026
- How to Calculate Standard Deviation and VarianceLearn what standard deviation measures, the difference between population and sample formulas, and how to read the result.Read guide Updated Sep 8, 2026
- How to Calculate Exact Age in Years, Months and DaysUnderstand how age is calculated across calendars, why leap years matter, and how to find total days or weeks lived.Read guide Updated Sep 8, 2026
- How to Add or Subtract Days and Find Date DifferencesLearn how date maths works across months and leap years, and how to find the days between two dates.Read guide Updated Sep 8, 2026
- How to Calculate the Duration Between Two TimesLearn how to compute hours and minutes between times, handle overnight spans, and total working hours.Read guide Updated Sep 8, 2026
- How Loan EMI Is Calculated (and How to Read It)Understand the EMI formula, how interest and principal split over time, and how to compare loan offers.Read guide Updated Sep 10, 2026
- How Mortgage Payments and Amortization WorkLearn how monthly mortgage payments are calculated, how amortization splits principal and interest, and what drives total cost.Read guide Updated Sep 10, 2026
- How Compound Interest Works (and How to Project Investment Growth)Understand the compound interest formula, how compounding frequency and regular contributions affect growth, and how to project future value.Read guide Updated Sep 10, 2026
Guides on converting length, weight, data, time zones, pressure, energy, number bases and fuel economy between units, with the formulas and worked examples.
- How to Convert Between Metric and Imperial UnitsLearn how unit conversion works, the key conversion factors, and how to avoid common measurement mistakes.Read guide Updated Sep 8, 2026
- How to Convert Between Time Units (Seconds, Hours, Days, Years)Understand time unit conversion, the quirks of months and years, and how to convert durations accurately.Read guide Updated Sep 8, 2026
- How to Convert Between Bytes, KB, MB, GB and TBLearn the binary (1024) vs decimal (1000) conventions for digital storage and how to convert between units accurately.Read guide Updated Sep 8, 2026
- How to Convert Network Speeds (Mbit/s, MB/s and More)Understand the difference between bits and bytes per second and how to convert network speeds accurately.Read guide Updated Sep 8, 2026
- How to Convert Between Pressure Units (bar, psi, pascal, atm)Learn the common pressure units, how they relate, and how to convert between them for engineering and everyday use.Read guide Updated Sep 8, 2026
- How to Convert Between Energy Units (joules, calories, kWh, BTU)Learn the main energy units, how they relate, and how to convert between them for food, electricity and engineering.Read guide Updated Sep 8, 2026
- How to Convert Numbers Between Binary, Octal, Decimal and HexUnderstand number bases, how conversion works, and why hex and binary are everywhere in computing.Read guide Updated Sep 8, 2026
- How to Convert Times Between World Time ZonesLearn how time zones and daylight saving work, how to convert times reliably, and how to schedule across zones.Read guide Updated Sep 8, 2026
- How to Convert Between Power Units (watts, kilowatts, horsepower)Learn the common power units, how they relate, and how to convert between them for engineering and appliances.Read guide Updated Sep 8, 2026
- How to Convert Fuel Economy (MPG, L/100km, km/L)Understand the different fuel economy units, why conversion is not a simple factor, and how to compare them.Read guide Updated Sep 8, 2026
Guides on JSON, Base64, regex, hashing, JWT, UUIDs, curl-to-code, YAML, HTML entities and cron — practical references for developers and security work.
- How to Format, Validate and Read JSONLearn what JSON is, how formatting and validation help, and how to fix common JSON errors.Read guide Updated Sep 8, 2026
- How Base64 Encoding Works (and When to Use It)Understand what Base64 is, how it encodes binary as text, and the common use cases and pitfalls.Read guide Updated Sep 8, 2026
- How to Write and Test Regular ExpressionsLearn how regex patterns work, how to test them safely, and practical patterns for everyday text tasks.Read guide Updated Sep 8, 2026
- How to Minify HTML and CSS (and Why It Helps)Learn what minification does, how much it saves, and how to minify code safely for production.Read guide Updated Sep 8, 2026
- How Hashing Works (MD5, SHA-256 and When to Use Each)Understand what a hash is, how MD5 and SHA-256 differ, and the safe vs unsafe uses of each.Read guide Updated Sep 8, 2026
- How JSON Web Tokens (JWT) Work and How to Decode ThemLearn the three parts of a JWT, what decoding reveals, and the security rules for using tokens safely.Read guide Updated Sep 8, 2026
- How UUIDs Work and When to Use ThemUnderstand what a UUID is, why collisions are astronomically unlikely, and the right uses for unique identifiers.Read guide Updated Sep 8, 2026
- How to Convert a curl Command Into CodeLearn how to read a curl command and translate it into fetch, Python or PHP requests automatically.Read guide Updated Sep 8, 2026
- How to Convert Between YAML and JSONLearn how YAML and JSON relate, why conversion is mostly mechanical, and the pitfalls to watch for.Read guide Updated Sep 8, 2026
- How HTML Entities Work (and When to Encode or Decode)Learn what HTML entities are, why encoding prevents bugs and XSS, and how to convert between text and entities.Read guide Updated Sep 8, 2026
- How Cron Expressions Work (and How to Build One)Understand the five fields of a cron expression, how to read them, and how to build schedules with confidence.Read guide Updated Sep 8, 2026
Guides on compressing, converting, resizing and cropping images, removing backgrounds, stripping EXIF metadata, optimizing SVGs and generating favicons.
- How Image Compression Works (and How to Shrink Images)Understand lossy vs. lossless compression, how quality affects size, and how to compress images for the web.Read guide Updated Sep 8, 2026
- How to Convert Images Between PNG, JPG, WebP and SVGLearn the strengths of each image format and how to convert between them for the right use case.Read guide Updated Sep 8, 2026
- How to Resize and Crop Images for Any PurposeLearn the difference between resizing and cropping, common social media sizes, and how to avoid distortion.Read guide Updated Sep 8, 2026
- How to Pick Colors and Extract Hex Codes From ImagesLearn how color codes work, how to sample colors from an image, and how to build a palette.Read guide Updated Sep 8, 2026
- How to Merge and Split PDF FilesLearn how PDF merging and splitting work, common scenarios, and how to do it in the browser.Read guide Updated Sep 8, 2026
- How to Remove an Image Background and Make It TransparentLearn how background removal works for solid-color backgrounds, how tolerance affects the result, and how to use it.Read guide Updated Sep 8, 2026
- How to Encode Images as Base64 Data URLsLearn how to embed images inline as Base64 data URLs, when it helps, and the trade-offs.Read guide Updated Sep 8, 2026
- How to Remove EXIF Metadata From Photos (and Why It Matters)Learn what EXIF data photos carry, the privacy risks, and how to strip metadata before sharing.Read guide Updated Sep 8, 2026
- How to Optimize and Minify SVG FilesLearn what makes SVGs larger than they need to be, how optimization helps, and how to shrink SVGs for the web.Read guide Updated Sep 8, 2026
- How to Create Favicons in Multiple SizesLearn what favicons are, the sizes you need, and how to generate them from a single image.Read guide Updated Sep 8, 2026
Guides on generating strong passwords, QR codes, random numbers, Lorem Ipsum, time-ordered UUID v7/ULID, dummy data and secret keys.
- How to Create Strong, Secure PasswordsLearn what makes a password strong, how length and character sets matter, and good password habits.Read guide Updated Sep 8, 2026
- How QR Codes Work and How to Generate ThemUnderstand what QR codes encode, how error correction lets them scan when damaged, and best practices for use.Read guide Updated Sep 8, 2026
- How Random Number Generators Work (and How to Use One)Learn the difference between random and pseudo-random, how no-repeat mode works, and common uses.Read guide Updated Sep 8, 2026
- How and When to Use Lorem Ipsum Placeholder TextLearn where Lorem Ipsum comes from, when placeholder text helps, and when you should replace it.Read guide Updated Sep 8, 2026
- How Time-Ordered UUID v7 and ULID Identifiers WorkUnderstand why time-ordered IDs are useful, how UUID v7 and ULID encode time, and when to prefer them.Read guide Updated Sep 8, 2026
- How to Generate Realistic Dummy Data for TestingLearn why realistic test data matters, what fields to generate, and how to export it as JSON or CSV.Read guide Updated Sep 8, 2026
- How to Generate Secure Secret Keys and API TokensLearn what makes a good secret key, how to generate one safely, and how to store it without leaking it.Read guide Updated Sep 8, 2026
Guides on BMI, BMR and daily calories, body fat percentage, water intake and pregnancy due dates — what the numbers mean and how they are estimated.
- How BMI Is Calculated (and How to Read It)Understand the BMI formula, what the categories mean, and the limitations of BMI as a health measure.Read guide Updated Sep 10, 2026
- How BMR and Daily Calorie Needs Are CalculatedLearn what BMR is, the Mifflin-St Jeor formula, and how activity level sets your daily calorie needs.Read guide Updated Sep 8, 2026
- How Body Fat Percentage Is Estimated (U.S. Navy Method)Learn how the U.S. Navy method estimates body fat from measurements, its accuracy, and how to take good measurements.Read guide Updated Sep 8, 2026
- How Much Water You Should Drink (and How It Is Estimated)Learn how daily water intake is estimated from weight and activity, and the factors that change your needs.Read guide Updated Sep 8, 2026
- How Pregnancy Due Dates Are CalculatedUnderstand how due dates are estimated from LMP or conception, what the weeks mean, and the limits of estimation.Read guide Updated Sep 8, 2026
Free how-to guides for every online tool
Every tool on Utilities Center ships with a standalone, keyword-targeted guide that explains the formula or method, walks through a worked example, and shows you when to use it and the common mistakes to avoid. The guides are written to capture the questions people actually search for — “how to unscramble letters”, “how is BMI calculated”, “how to format JSON”, “how to generate a strong password” — so you can learn the concept, then jump straight into the tool.
Popular guides
- How to unscramble letters into words — Scrabble and anagram strategy.
- How percentages are calculated — percent of a number, increase and decrease.
- How loan EMI is calculated — the amortization formula, step by step.
- How compound interest works — future value with regular contributions.
- How to format and validate JSON — syntax, indenting and error finding.
- How to create a strong password — length, entropy and character sets.
- How image compression works — lossy vs lossless and quality trade-offs.
- How BMI is calculated — the formula, categories and limitations.
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