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The Prime Webkit blog

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Practical writing on file optimization, careers, web performance, and building online — from the studio behind the tools.

Calculators

Percentage Calculator Formula: Formulas and Worked Examples

Learn the percentage calculator formula for percentages of a number, percentage increase and decrease, and percentage difference with clear worked examples.

September 2, 20266 min read

Popular guides

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Text

Text Case Converter: Uppercase, Lowercase, Title Case and More

A practical guide to text case — when to use Title Case vs Sentence case, what camelCase and snake_case are for, and how to convert between them instantly.

Image

How to Build a Colour Palette (and Pull Colours From Any Image)

Understand HEX, RGB, and HSL, learn how colour harmonies work, and see how to generate a palette or extract one from an image — free and in your browser.

Text

How to Compare Two Texts and Spot Every Change

A text diff shows exactly what changed between two versions. Here's how to compare drafts, contracts, and configs — and read the results with confidence.

Developer

JWT Decoder Online: How to Read a Token Safely

JSON Web Tokens power modern auth. Learn how to read the header, payload, and claims of a JWT — and why decoding is never the same as verifying.

Developer

Timestamp Converter: Unix Epoch Time Made Simple

What a Unix timestamp is, why software stores time as a number, and how to convert between epoch seconds and human dates — in seconds or milliseconds.

Text

How to Create a URL Slug (and Why It Matters for SEO)

A clean URL slug helps SEO, sharing, and usability. Learn the rules for good slugs and how to turn any title into one instantly.

Text

Word Count, Character Count, and Reading Time — Explained

Why word and character limits exist, how reading time is estimated, and how to track it all live as you write, privately in your browser.

Calculators

Percentage Calculator Online: A Practical Guide With Examples

The four percentage problems that cover almost everything — percent of a number, percent change, and adding or subtracting a percentage — explained with real examples.

Image

Remove Background From Image Online: 3-Step Free Guide

Remove background from image online in three practical steps with a free browser tool. Learn how to cut out product, profile, and ID photos without signup.

Developer

URL Encoder and Decoder: Encoding Explained

What %20 and %2F actually mean, when you need to encode a URL, and how to encode or decode query strings correctly — with the component vs full-URL distinction.

Image

Remove Background From Image Online: 3-Step Free Guide

Remove background from image online in three practical steps with a free browser tool. Learn how to cut out product, profile, and ID photos without signup.

September 2, 20267 min read
Image

How to Crop an Image Online (Free, No Upload)

Cropping is the fastest way to improve a photo. Here's how to crop to the right aspect ratio for avatars, thumbnails, and social posts — privately, in your browser.

April 2, 20265 min read
PDF

How to Unlock a PDF (Remove Restrictions You're Allowed to Remove)

The difference between PDF passwords, when you can legitimately remove restrictions, and how to unlock a PDF you own in your browser without uploading it.

March 30, 20265 min read
Career & Business

How to Create a Signature Online (Free Transparent PNG)

Draw or type a signature, export a clean transparent PNG, and drop it into contracts, PDFs, and emails — all in your browser, with nothing uploaded.

March 28, 20265 min read
Career & Business

How to Generate a Business Name That Actually Works

A practical framework for naming a business or brand — what makes a name work, mistakes to avoid, and how to brainstorm dozens of ideas from a few keywords.

March 26, 20265 min read
Text

Text Case Converter: Uppercase, Lowercase, Title Case and More

A practical guide to text case — when to use Title Case vs Sentence case, what camelCase and snake_case are for, and how to convert between them instantly.

March 25, 20265 min read
Text

What Is Lorem Ipsum? (And How to Generate Placeholder Text)

Where lorem ipsum comes from, why designers use placeholder text instead of real copy, and how to generate exactly the amount you need.

March 24, 20265 min read
Text

How to Turn Text Into Speech (Free, In Your Browser)

Why reading text aloud helps you proofread, learn, and stay accessible — plus how text-to-speech works and how to use it privately without any downloads.

March 22, 20264 min read
Text

How to Remove Line Breaks From Text (The Clean Way)

Text copied from PDFs and emails often arrives with a break on every line. Here's how to remove or normalise line breaks without mangling your paragraphs.

March 22, 20265 min read
Text

How to Compare Two Texts and Spot Every Change

A text diff shows exactly what changed between two versions. Here's how to compare drafts, contracts, and configs — and read the results with confidence.

March 20, 20265 min read
Image

How to Build a Colour Palette (and Pull Colours From Any Image)

Understand HEX, RGB, and HSL, learn how colour harmonies work, and see how to generate a palette or extract one from an image — free and in your browser.

March 19, 20264 min read
Text

How to Create a URL Slug (and Why It Matters for SEO)

A clean URL slug helps SEO, sharing, and usability. Learn the rules for good slugs and how to turn any title into one instantly.

March 18, 20265 min read
Developer

URL Encoder and Decoder: Encoding Explained

What %20 and %2F actually mean, when you need to encode a URL, and how to encode or decode query strings correctly — with the component vs full-URL distinction.

March 16, 20266 min read
Developer

What Is a UUID? (And How to Generate One Safely)

UUIDs are the unique IDs behind modern software. Learn what they are, why v4 is the one you usually want, and how to generate them securely in bulk.

March 14, 20265 min read
Developer

How to Generate a Hash (SHA-256 and Friends), Explained

What a hash is, why SHA-256 is everywhere, why MD5 is dead, and how to generate a hash from text in your browser for checksums and fingerprints.

March 12, 20265 min read
Developer

JWT Decoder Online: How to Read a Token Safely

JSON Web Tokens power modern auth. Learn how to read the header, payload, and claims of a JWT — and why decoding is never the same as verifying.

March 10, 20266 min read
Developer

How to Test a Regular Expression (Without Losing Your Mind)

Regex is powerful and famously fiddly. Learn a practical way to build and test patterns, understand flags, and debug matches in real time.

March 8, 20266 min read
Developer

Timestamp Converter: Unix Epoch Time Made Simple

What a Unix timestamp is, why software stores time as a number, and how to convert between epoch seconds and human dates — in seconds or milliseconds.

March 6, 20265 min read
Image

How to Resize an Image Online Without Losing Quality

Everything you need to know about resizing images the right way: pixels vs. percentage, why aspect ratio matters, and how to resize privately in your browser.

March 4, 20265 min read
Image

PNG to JPG, JPG to WebP: How to Convert Image Formats (and Which to Use)

A plain-English guide to JPG, PNG, and WebP — what each is good at, when to convert between them, and how to do it privately in your browser.

March 1, 20265 min read
PDF

How to Convert a PDF to JPG — Every Page, Free and Private

Turn PDF pages into images for thumbnails, previews, and slides. Here's when to convert PDF to JPG vs PNG, how to keep pages crisp, and how to do it in your browser.

February 25, 20265 min read
PDF

How to Split a PDF: Extract Pages the Easy Way

Whether you need one page or a clean set of separate files, here's how PDF splitting works, when to use it, and how to do it privately in your browser.

February 21, 20265 min read
Developer

How to Create a Strong Password (and Why Length Beats Complexity)

What actually makes a password hard to crack, the myths that waste your time, and how to generate genuinely strong passwords privately in your browser.

February 17, 20265 min read
Text

Word Count, Character Count, and Reading Time — Explained

Why word and character limits exist, how reading time is estimated, and how to track it all live as you write, privately in your browser.

February 13, 20265 min read
Career & Business

How to Create a Professional Invoice (Free Guide for Freelancers & Small Businesses)

What every invoice must include to get paid on time, common mistakes that cause delays, and how to create a clean invoice PDF for free in your browser.

February 9, 20265 min read
Calculators

Unit Conversion Made Simple: Metric, Imperial, and Everything Between

A practical guide to converting length, weight, temperature, and more — the formulas worth knowing, the conversions people get wrong, and a free tool that does it all.

February 5, 20265 min read
Calculators

How to Calculate Your Loan EMI (With Worked Examples)

Understand exactly how a loan or mortgage monthly payment is worked out, what drives the total interest you pay, and how to model it all instantly for free.

February 1, 20266 min read
PDF

How to Convert PDF to Word — Free, and Without Uploading Your Files

A practical guide to converting a PDF into an editable Word document, why most online converters ask you to upload sensitive files, and how to do it privately in your browser.

January 19, 20266 min read
PDF

How to Convert Word to PDF for Free (and Keep Your Formatting Intact)

Why you should send a PDF instead of a .docx, how Word-to-PDF conversion preserves your layout, and how to convert a document in your browser without installing Office.

January 16, 20265 min read
PDF

How to Convert JPG to PDF (and Combine Several Images into One File)

Turn photos and scans into a single, tidy PDF — the right way to submit documents, receipts, and portfolios. Do it in your browser with no upload and no watermark.

January 13, 20265 min read
PDF

How to Merge PDF Files Into One (Free, Private, and In Your Browser)

The clean way to combine multiple PDFs into a single document, control the page order, and do it without uploading confidential files to a third-party server.

January 10, 20265 min read
Image

Remove Background From Image Online: Free Guide

A practical guide to cutting out a subject and exporting a clean transparent PNG — what works, what to shoot for, and how to do it privately in your browser.

January 7, 20265 min read
Career & Business

How to Create a QR Code — Links, Wi-Fi, and Contact Cards

A complete guide to making QR codes that actually work: which type to choose, why static beats 'dynamic' for most people, and how to make one free with no tracking.

January 4, 20266 min read
Calculators

How to Calculate Your Exact Age in Years, Months, and Days

Working out an exact age is trickier than it looks, thanks to leap years and uneven months. Here's how age calculation really works and how to get an exact answer instantly.

January 2, 20265 min read
Calculators

Percentage Calculator Online: A Practical Guide With Examples

The four percentage problems that cover almost everything — percent of a number, percent change, and adding or subtracting a percentage — explained with real examples.

December 29, 20255 min read
Shopify

Shopify vs. WooCommerce: Which Is Right for Your Store?

The two biggest e-commerce platforms, compared honestly. Shopify's simplicity vs. WooCommerce's flexibility — here's how to choose the right one for your business.

December 20, 20253 min read
Shopify

How to Increase Your Shopify Conversion Rate

More traffic is expensive; a higher conversion rate is permanent. Here are the highest-impact ways to turn more of your Shopify visitors into paying customers.

December 19, 20253 min read
Web Development

How Much Does Web Development Cost in 2025? A Real Breakdown

What a website actually costs — from simple marketing sites to custom web apps — and the factors that move the price. An honest, no-jargon pricing guide.

December 18, 20254 min read
Shopify

Migrating to Shopify: A Step-by-Step Guide (Without Losing SEO)

Replatforming to Shopify sounds daunting, but a careful migration preserves your products, customers, and rankings. Here's how to do it right, step by step.

December 17, 20253 min read
Web Development

Custom vs. Template Websites: Which Is Right for Your Business?

Templates are cheap and fast; custom builds are distinctive and powerful. Here's how to decide which approach fits your business, goals, and budget.

December 16, 20253 min read
Software Development

How Much Does Custom Software Cost?

Custom software pricing explained — what drives the cost, realistic ranges for different project types, and how to control your budget by starting with the right MVP.

December 15, 20253 min read
WordPress

Why Businesses Choose WordPress (And When They Shouldn't)

WordPress powers a huge share of the web. Here's why so many businesses choose it, what it's genuinely great at, and when another platform might serve you better.

December 14, 20253 min read
Software Development

Build vs. Buy Software: How to Make the Right Call

Should you build custom software or buy an off-the-shelf tool? A practical framework for making the decision that saves money and headaches — in either direction.

December 13, 20253 min read
WordPress

7 Common WordPress Security Mistakes (And How to Fix Them)

Most WordPress hacks come down to a handful of avoidable mistakes. Here are the seven most common — and exactly how to protect your site from each.

December 12, 20253 min read
Software Development

The MVP Development Guide: Build Less, Learn More

A Minimum Viable Product lets you validate your idea fast and cheap before committing to a full build. Here's how to scope and build an MVP the right way.

December 11, 20253 min read
WordPress

How to Optimize a WordPress Website for Speed

Slow WordPress site? Here are the highest-impact ways to speed it up — from hosting and caching to images and plugins — and why speed drives both conversions and rankings.

December 10, 20253 min read
Backend Development

REST vs. GraphQL: Which API Style Should You Use?

REST and GraphQL are the two dominant ways to build APIs. Here's a clear, jargon-light comparison to help you choose the right one for your project.

December 9, 20253 min read
SEO

Technical SEO Best Practices: The Foundation of Rankings

Technical SEO is the groundwork that lets your content rank. Here are the best practices that make your site fast, crawlable, and understandable to search engines.

December 8, 20253 min read
Backend Development

Database Design Basics Every Business Should Understand

Your database holds your most valuable asset — your data. Here are the database design fundamentals that keep applications fast, reliable, and ready to scale.

December 7, 20253 min read
SEO

Local SEO Strategies That Generate Leads

For location-based businesses, local SEO is where the highest-intent leads are. Here are the strategies that get you into the map pack and in front of ready-to-buy customers.

December 6, 20253 min read
Backend Development

Why Backend Architecture Matters More Than You Think

Users never see the backend, but they feel it in every fast response and every feature that just works. Here's why backend architecture makes or breaks your product.

December 5, 20253 min read
SEO

The Practical SEO Guide for Small Businesses

SEO can feel overwhelming for a small business. This practical guide cuts it down to the fundamentals that actually move the needle — no jargon, no fluff.

December 4, 20253 min read
Career

Building an ATS-Friendly Resume: What Actually Gets You Past the Filter

Most resumes are read by software before a human sees them. Here's what applicant tracking systems look for, the formatting mistakes that get you filtered out, and how to build a clean CV for free.

December 2, 20252 min read
Digital Marketing

How Digital Marketing Increases Revenue (Not Just Traffic)

Digital marketing should grow your revenue, not just your traffic. Here's how the pieces actually connect to sales — and how to stop wasting spend on vanity metrics.

December 2, 20253 min read
Digital Marketing

PPC vs. SEO: Which Should Your Business Invest In?

Paid ads deliver instant traffic; SEO builds compounding organic growth. Here's an honest comparison to help you decide where to put your marketing budget.

November 30, 20253 min read
Digital Marketing

Social Media Marketing Strategies That Actually Work

Beyond posting and hoping — here are the social media marketing strategies that build audiences, drive traffic, and generate real leads for your business.

November 28, 20253 min read
AI & Chatbots

How AI Chatbots Improve Customer Support

Modern AI chatbots resolve questions instantly, cut support costs, and keep customers happy 24/7. Here's how they actually improve support — and where humans still matter.

November 26, 20253 min read
PDF

How to Reduce PDF File Size for Email (Without Losing Readability)

Your PDF is too big to email? Here's why PDFs balloon in size, the fastest ways to shrink them, and how to do it privately without uploading confidential documents.

November 25, 20252 min read
AI & Chatbots

The Benefits of Custom AI Assistants for Business

Off-the-shelf AI is generic. A custom AI assistant trained on your business understands your products, answers accurately, and works exactly how you need. Here's why that matters.

November 24, 20253 min read
AI & Chatbots

AI Automation for Businesses: Where to Start

AI automation can save your team hours every week — if you target the right tasks. Here's a practical look at what to automate, how it works, and how to start small.

November 22, 20253 min read
Image

How to Compress Images Without Losing Quality (2025 Guide)

A practical guide to shrinking JPG, PNG, and WebP images for the web — what actually causes quality loss, the right settings to use, and how to do it privately in your browser.

November 18, 20252 min read