Everyday answers, in 38 free calculators
Money, salary, units, dates, AI costs — every tool runs instantly in your browser. No sign-up, and your numbers never leave your device.
AI Cost Intelligence
SpecializedOur deep-dive suite — live pricing, real budgets, real decisions.
AI Model Cheat Sheet
Every model's price, context window & best use — one page, updated monthly.
Compare🤖AI API Cost Calculator
Estimate and compare your monthly bill across 26 GPT, Claude & Gemini models.
Estimate🔢Token Calculator
Paste any text — see its token count and what it costs on every model.
Simulate💬Chatbot Cost Simulator
Users × messages × tokens: budget your AI product before you build it.
Decide⚖️Subscription vs API
Is ChatGPT Plus worth $20/month for you? Find your break-even point.
Track📉AI Price Tracker
Every model's current price + a monthly changelog of cuts and releases.
Benchmark📊Real-Task Cost Benchmarks
Not price per token — price per job. 8 real tasks across all 26 models.
AI & Dev Tools11 tools · in-depth
Money & Loans4 calculators
Salary & Work3 tools
Unit Conversion2 tools
Everyday Math3 calculators
Dates & Time3 calculators
Health1 calculator
Images9 tools
PDF & Documents3 tools
Text & Security6 tools
Money & Loans
🏠Mortgage Calculator
Full PITI payment, amortization schedule, and extra-payment savings.
💳Loan Calculator
Monthly payment and total interest for any personal or auto loan.
📈Compound Interest
How savings grow with monthly contributions and compounding.
🏷️Discount Calculator
Sale price and savings — including stacked "extra % off" deals.
Salary & Work
💼Salary to Hourly
Your true hourly rate — with real hours and vacation weeks.
🧾Take-Home Pay (2026)
Salary after federal tax, FICA, 401(k), and state tax.
📋Salary Breakdowns
Every salary from $25k to $300k, per hour, week, and month.
Unit Conversion
🔁Unit Converter
Length, weight, temperature, volume, area & speed in one tool.
📐Conversion Reference
Every factor at full precision — length, weight, volume, area, speed, temperature.
AI & Developer Tools
🤖AI API Cost Calculator
Compare GPT, Claude & Gemini pricing and estimate your bill.
💠AI Pricing by Provider
Every tracked model priced and compared within its provider lineup.
Everyday Math
％Percentage Calculator
X% of a number, percent of Y, and increase/decrease.
🍽️Tip Calculator
Tip, total, and per-person share when splitting the bill.
🛒Discount Calculator
What you actually pay after the sale sticker.
Dates & Time
📅Date Calculator
Days between dates (with business days), add/subtract days.
🎂Age Calculator
Exact age in years, months, days — plus next-birthday countdown.
Health
Images
✂️Background Remover
AI cutout to a transparent PNG — your photo never leaves your browser.
🖼️Image Compressor
Shrink JPG/PNG/WebP file size in your browser — nothing is uploaded.
🔄Image Converter
HEIC to JPG, WebP to PNG — convert between formats locally.
🕵️EXIF Viewer & Remover
See hidden GPS and camera metadata in photos — and strip it out.
✂Crop for Social Media
YouTube thumbnail, Instagram, and profile-circle presets with drag & zoom.
⭐Favicon Generator
One image to every favicon size plus a real .ico — zipped.
💧Watermark Tool
Add a text or logo watermark to photos — corners or tiled.
📄Image to Base64
Data URI generator with ready-made HTML and CSS snippets.
⚪Round Corners & Circle
Rounded corners or circle crop to a transparent PNG.
PDF & Documents
📎Merge PDF
Combine several PDFs into one, in the order you choose — no upload.
🖼️JPG to PDF
Turn photos and images into a single PDF document.
✂️Split PDF
Extract a page range, or save every page as its own PDF.
Text & Security
✍️Word Counter
Live word, character, sentence counts and reading time.
🔐Password Generator
Strong random passwords, generated locally in your browser.
▦QR Code Generator
Any link or text to a downloadable QR code — all in your browser.
🔗URL Shortener
Turn a long link into a short, shareable one — free, no sign-up.
🔠Case Converter
UPPERCASE, lowercase, Title Case, camelCase, snake_case in one click.
⏱️Timestamp Converter
Unix epoch time to readable date and back — live current timestamp.
🆚Diff Checker
Compare two texts line by line and see exactly what changed.
Guides
🪟AI Context Windows Explained: Why They Quietly Drive Your Bill
A context window isn't just a size limit — every token inside it gets billed on every call. What fills it up, and how to manage the cost.
🔢Base64: When It's Actually the Right Tool
Base64 isn't compression or encryption — it's text-safe encoding at a 33% size cost. When that trade genuinely helps, and when it just bloats a file.
🖨️Print vs. Web Resolution: Why the Same Photo Fails in Either One
A photo sharp enough for a website can print blurry, and a print-ready file is needlessly heavy online. The pixel math behind resolution, and how to size an image for each.
📧Email Attachment Size Limits: Gmail, Outlook, Yahoo & iCloud Compared
Gmail, Outlook, Yahoo, and iCloud each cap attachments at a different size, and base64 encoding eats into whatever the number says.
💳Compound Interest and Credit Card Debt: Why the Balance Barely Moves
Credit card interest compounds daily, not annually — why minimum payments crawl, and how that differs from a simple-interest loan.
🔀Diff Tools for Writers: Comparing Text Without Losing Your Mind
How writers, students, and editors can use text comparison to track revisions, catch sneaky edits, and settle 'what actually changed' arguments.