Learn the stuff
they don't teach in school
Real-world guides on taxes, finance, business, code, and design — written by people who actually do this for a living. Updated for 2026.
Photo & ID
Passport, visa, and ID photo requirements
Taxes
Income tax, self-employment tax, and quarterly estimates
Self-Employment Tax 2026: Stop Overpaying
Freelancers: you're probably paying more SE tax than you need to. Here's how to calculate it right, claim every deduction, and avoid those nasty quarterly penalties.
Crypto Taxes in 2026: What the IRS Actually Knows
The IRS gets Form 1099-DA now. Here's how to calculate capital gains, handle DeFi and swaps, and avoid the #1 mistake that triggers audits.
W-2 vs 1099: That $100K Contract Is Really $72K
The 25-40% pay gap no one talks about. Health insurance, retirement match, PTO, unemployment — when you add it all up, that contractor rate isn't what it seems.
1099-K Changes: The $600 Threshold Hits Everyone
If you sold $600+ on eBay, Etsy, or Venmo this year, the IRS now knows about it. Here's what you owe, what you can deduct, and how to avoid penalties.
Quarterly Taxes for Freelancers: Don't Wait Until April
If you owe $1,000+ at tax time and didn't make quarterly payments, the IRS adds a penalty. Here's when each payment is due and how to calculate the right amount.
Freelancer Tax Brackets 2026: How Much Tax Do I Pay?
See exactly how much tax a freelancer pays at $40K, $80K, and $150K income levels — SE tax, federal brackets, QBI deduction, and state tax broken down with real examples.
Sales Tax Nexus 2026: When Must You Collect?
The $100K/200-transaction rule, marketplace facilitator laws, and the 5 states with no sales tax. Know exactly when you must register, collect, and remit.
Capital Gains Tax 2026: Short-Term vs Long-Term Rates
Hold a stock for 364 days and you pay 22%. Hold it one day longer and you pay 15%. Here's the 0/15/20% bracket breakdown and the NIIT surtax that catches high earners.
W-4 Withholding: Stop Giving the Government a Free Loan
If you got a $3,000 refund, you overpaid $250/month all year. A perfect W-4 gets your refund close to zero. Here's how to fill out Steps 2-4 for 2026.
EU VAT Calculator: Forward, Reverse, and B2B Explained
VAT is 27 different rates across the EU. Add reverse charge for B2B and cross-border rules — here's how to calculate VAT correctly for any EU country in 2026.
Paycheck Math: What $75,000 Salary Actually Pays You
Your $75,000 salary becomes $55,000 after federal tax, state tax, FICA, and benefits. Here's exactly where every dollar goes and how to estimate take-home pay in any state.
Personal Finance
Mortgage, retirement, investing, and compound interest
Mortgage Amortization: Where Your Money Actually Goes
Spoiler: for the first 5 years, almost all your payment is interest. Here's how to flip that equation and build equity faster without refinancing.
401(k) vs Roth IRA: The Honest Answer
Everyone says "it depends." Here's what it actually depends on — your tax bracket now vs. in retirement, employer match, and the one scenario where Roth always wins.
Compound Interest: Why Starting Early Beats Saving More
Someone who saves $200/month from age 25 ends up with more than someone saving $500/month from age 40. The math is wild — and it works against you with debt too.
Rental Property ROI: Your "8% Return" Is Actually 22%
Cash flow is only part of the story. When you add appreciation, equity paydown, and depreciation tax benefits, real rental returns blow past stocks — if you account for the hidden costs.
HSA vs FSA: The Triple-Tax Advantage Nobody Told You About
One account rolls over forever and grows tax-free. The other confiscates your money at year-end. Here is the real math on which one saves you more — and why the HSA is a stealth retirement account.
Car Loan Math: What That $400/Month Payment Really Costs
A $35,000 car at 7% APR for 72 months costs $43,000. The monthly payment looks affordable; the total interest does not. Here's the real math.
Student Loan Payoff: SAVE vs IBR vs Refinance
The SAVE plan caps payments at 5% of discretionary income. IBR forgives after 20 years. Refinancing locks in a rate but loses forgiveness. Here's the real math on each path.
Life Insurance: How Much Coverage You Actually Need
The DIME method gives you a real number in 5 minutes — no agent upselling, no vague rules of thumb. Here's how to calculate exactly how much your family needs.
GLP-1 Medication Costs: Ozempic vs Wegovy vs Mounjaro
GLP-1 drugs cost $900-1,300/month without insurance. With coupons and savings cards, some patients pay $25. Here's how to find the real price at each pharmacy.
Estate Tax Explained: Will Your Heirs Actually Owe?
The federal estate tax exemption is $13.99 million. But 17 states have their own estate tax with thresholds as low as $1 million. Here's how to calculate what you might owe.
Business & Legal
LLC, privacy, cookie consent, payment processing, and side hustles
LLC Formation: Which State Actually Saves You Money?
Wyoming sounds cheap until you see the registered agent fees. Here's the real 5-year cost comparison across all 50 states — formation, annual reports, and franchise tax.
Cookie Consent in 2026: Google Now Requires Consent Mode v2
If you use Google Analytics or AdSense, you need Consent Mode v2 — or your data stops flowing. Here's how to add a compliant banner in under 5 minutes.
Privacy Policy Checklist: 9 Things Yours Is Probably Missing
GDPR fines hit 4% of global revenue. CCPA is $7,500 per violation. Most small sites are missing at least 3 required sections — here's exactly what to add.
Stripe vs PayPal vs Square: What You Actually Pay Per $1,000
They all say 2.9% + 30¢. But add in chargebacks, currency conversion, holds, and payout delays — and the real cost tells a different story.
Break-Even Analysis: The Number That Keeps Businesses Alive
Before you set your price, you need one number: how many sales to cover costs. Everything after that is profit. Here's how to find your break-even point.
Invoices That Actually Get Paid (On Time)
The #1 reason payments are late? Bad invoices. Missing details, unclear terms, and no payment link. Here's the anatomy of an invoice that gets paid fast.
Copyright & Public Domain: What You Can Actually Use for Free
That 1960 photo isn't necessarily public domain. Here's how to check — and the one rule change in 2023 that affected millions of works.
Dropshipping Profit: Your "30% Margin" Is Actually 5%
Product cost is just the start. Platform fees, payment processing, ad spend, and taxes eat your margin alive. Here's how to calculate your real profit per order.
Time Zone Conversion: Finding Meeting Times That Actually Work
When New York is 9 AM, London is 2 PM, but Sydney is already midnight. Here's how to find meeting times across time zones without making everyone miserable.
USCIS Processing Times: How Long Will Your Case Actually Take?
USCIS says 80% of cases finish within a posted time range. Here's what that means, how to check your form and service center, and why some cases take 3x longer.
Green Card Priority Dates: When Will Yours Become Current?
Your priority date determines when you can file your green card. The Visa Bulletin moves forward, backward, and sometimes not at all. Here's how to read it and estimate your wait.
Image Tools
Formats, resizing, watermarks, and WebP conversion
PNG vs JPG vs WebP: Stop Using the Wrong Format
Using PNG for photos? Your pages are 3x heavier than they need to be. Using JPG for logos? Hello, compression artifacts. Here's the right format for every situation.
Watermarking Your Photos: What Actually Deters Theft
A tiny logo in the corner? That's cropped off in 2 seconds. Here's how to watermark so it protects your work without ruining the image.
Favicon in 2026: You Need More Sizes Than You Think
Just one favicon.ico? That was 2010. Now you need 16×16, 32×32, 48×48 for Windows, 180×180 for Apple Touch, 192 + 512 for Android. Here's the complete list.
Image Resizing: Why Your Photos Look Blurry on the Web
Uploading a 4000px photo to display at 800px? That's why your site is slow. Here's the right dimensions for every platform — web, social, print, email.
WebP: The Easiest 30% Speed Boost Your Site Can Get
Converting images to WebP makes your site 25-35% faster — same quality, smaller files. Both Lighthouse and Google PageSpeed literally tell you to do this. Here's how.
AI Tools
Resume rewriting, contract analysis, email writing, invoice extraction, and AI productivity
AI Background Removal & Upscaling: How Good Is It Really?
We tested AI background removal on 50 tricky images — hair, glass, shadows. The results? Surprisingly good for simple backgrounds, frustrating for complex ones. Here's when to trust it.
Grammar Checkers: What They Catch and What They Miss
Browser-based grammar checkers run 200+ rules without sending your text to a server. Here's what they detect, what they miss, and when you still need a human.
Prompt Engineering: Writing Instructions AI Models Actually Follow
The difference between a good prompt and a bad prompt is the difference between a useful answer and a hallucination. Here's how to structure prompts that work.
AI Resume Rewriting: ATS Optimization Without Uploading Your Data
Learn how browser-based AI rewrites your resume for ATS, what keyword match scores mean, and how to use local LLMs to improve your bullet points — 100% private.
AI Contract Analysis: Finding Risky Clauses Without a Lawyer
Discover how browser-based AI scans contracts for auto-renewal, unlimited liability, hidden fees, and non-compete clauses — all locally, no upload required.
AI Email Writing: Draft Professional Emails Without a Cloud
Learn how browser-based AI writes professional business emails — follow-ups, negotiations, apologies, and cold outreach — all locally in your browser.
AI Invoice Extraction: Automate Data Entry Without Cloud OCR
Learn how browser-based AI extracts data from invoices and receipts — vendor, date, amounts, line items — all locally without uploading financial documents.
Workflows
Step-by-step guides connecting tools into complete business, family, and creator workflows
Small Business Launch Workflow: From LLC to First Invoice
A step-by-step guide to launching a small business: choose your state for LLC, calculate break-even, generate legal pages, create your first invoice, and set up tax tracking.
Reseller Workflow: From Sourcing to Profit
A complete guide for online resellers: calculate true profit after fees, check sales tax nexus, handle 1099-K reporting, and find your break-even.
Family Management Workflow: Budgets, Moves, and Digital Estate
A step-by-step guide for managing your household: build a family budget, audit subscriptions, plan a move, and organize your digital estate — all with free tools.
Creator Workflow: From Image Editing to YouTube SEO
A step-by-step guide for content creators: resize images for every platform, generate AI captions, optimize YouTube videos, and convert formats — all with free browser tools.
Creator & Video
YouTube SEO, captions, and QR codes
YouTube Titles: The 5 Things That Actually Affect Ranking
It's not just keywords. Title length, power words, year, emotional triggers, and (yes) clickbait avoidance all factor in. Here's the formula that works in 2026.
SRT Captions: Why 17 Characters Per Second Is Your Limit
If viewers can't read your captions before they disappear, they stop watching. Here's how to fix timing, convert between SRT and VTT, and handle the CPS limit.
QR Codes in 2026: Static vs Dynamic and Why It Matters
Static QR codes are forever — if the URL changes, you're reprinting everything. Dynamic codes let you change the destination. Here's when each one makes sense.
Merge, split, convert, sign, and unlock PDF documents
How to Merge PDF Files Without Losing Quality
Most free PDF mergers upload your documents to a server and strip bookmarks. Here's how to combine PDFs locally, preserve metadata, and get the page order right for legal documents.
PDF to Word Conversion: What Actually Works in 2026
Converting PDF to editable Word sounds easy until you get garbage formatting. Here's why tables break, how OCR introduces errors, and which method preserves your document.
Splitting PDFs: Extract Pages the Right Way
Need just pages 3-7 from a 200-page PDF? Learn how to split by range, size, or bookmarks — and why the wrong method creates broken links and missing metadata.
Removing PDF Passwords: What You Need to Know
Forgot your PDF password? Learn the difference between user and owner passwords, why removing print/copy restrictions is instant, and when it's legal.
Image to PDF: The Right Way to Combine Photos
Turning JPG, PNG, and WebP images into a PDF sounds trivial, but page size, orientation, and DPI choices determine whether the result looks professional or like a phone dump.
Signing PDFs Electronically: A Practical Guide
Electronic signatures are legally binding in the US and EU. But not all e-signatures are equal. Here's the difference between a drawn signature and a digital certificate.
Developer
JSON, JWT, regex, hashes, Markdown, diff, and other dev utilities
JSON Errors: The 5 That Waste 80% of Your Debug Time
Trailing commas. Missing quotes. Unescaped characters. These five JSON errors account for almost all parsing failures. Here's how to spot them fast.
JWT Tokens: The 3 Security Mistakes You're Probably Making
Accepting "alg: none," storing tokens in localStorage, not checking expiration — these three mistakes appear in roughly half of JWT implementations. Here's the fix for each.
MD5 Is Broken. SHA-1 Is Broken. Here's What to Use Instead.
If you're still using MD5 for anything security-related, stop. Collision attacks are practical and cheap. Here's when to use SHA-256 vs SHA-512, and why raw hashes are bad for passwords.
URL Encoding: The Bug That Happens When You Use the Wrong Function
encodeURI and encodeURIComponent produce different results. Pick the wrong one and your API calls silently fail. Here's the one rule that keeps you safe.
Regex Without the Headache: A Visual Cheat Sheet
Nobody memorizes regex. The trick is understanding 5 building blocks — character classes, quantifiers, groups, anchors, and flags — and combining them. Here's how.
Unix Timestamps: The #1 Bug Source in Every Codebase
JavaScript uses milliseconds. APIs use seconds. Mix them up and your dates show 1970. This one mismatch causes more bugs than any other datetime issue. Here's the fix.
UUID v4: 122 Bits of Randomness That Scale Globally
No central coordinator, no collision risk, works across every database and microservice. Here's why UUIDs are the default choice for distributed systems — and when they're not.
WCAG Contrast: That Light Gray Text Is Failing 15% of Users
One in seven people has some form of vision impairment. If your text-background contrast is below 4.5:1, they can't read it. Here's how to pick colors that work for everyone.
Passwords in 2026: "Correct Horse Battery Staple" Still Wins
Length beats complexity. "Tr0ub4dor&3" takes 3 days to crack. "correct horse battery staple" takes 550 years. Here's why passphrases changed the security game.
Base64: When to Use It (and When It Makes Things Worse)
Base64 increases file size by 33%. That's fine for embedding small images in CSS or API tokens, but terrible for large files. Here's the line where it stops making sense.
camelCase vs snake_case: Every Language's Convention in One Place
JavaScript: camelCase. Python: snake_case. CSS: kebab-case. SQL: SCREAMING_SNAKE. Don't mix them — here's the standard for every language you'll use.
Markdown: Write Once, Publish Everywhere
READMEs, documentation, blog posts, Notion pages — Markdown is the format that works everywhere. Here's everything you need, from basic syntax to GFM tables and task lists.
Diff Checkers: Catch the One Word They Changed in Your Contract
They sent you a "minor revision" — but buried on page 4, the liability cap doubled. A diff checker finds every change in seconds. Here's how to use one effectively.
CSV ↔ JSON: The Conversion Pitfalls Nobody Warns You About
Commas inside values, newlines in fields, European semicolons, nested objects that don't flatten cleanly — here's what breaks when converting between the two most common data formats.
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