Calculators that show their working
Each tool answers one specific question, explains the math behind the answer, and runs entirely in your browser. No sign-up, no tracking of what you type.
Free · No sign-up · Runs in your browser
- Perimeter: 2 × (60 + 72)264 in
- Add for joins and corners+ 12 in
- Binding needed276 in
- Strips: 276 ÷ 42, rounded up7
- Fabric: 7 × 2.5 in17.5 in
Buy½ yard
Open the binding calculatorAll tools
Every calculator shows the formula, a worked example and its sources.
Paycheck & local tax
Browse 5 tools- No. 01DC PaycheckTake-home pay after federal, FICA and DC income tax.
- No. 02Philadelphia Wage TaxCity wage tax at 2026 rates, for residents and commuters.
- No. 03Detroit Income TaxDetroit city tax plus Michigan’s 4.25%, with exemptions.
- No. 04Ohio City Income TaxWork city vs home city, with each city’s credit rules.
- No. 05PA Local EITResident vs non-resident rate, plus the Local Services Tax.
Craft & making
Browse 5 tools- No. 06Epoxy ResinResin volume for tables, trays and river tables.
- No. 07Candle WaxWax and fragrance oil to weigh for any jar and batch.
- No. 08Quilt BindingStrips to cut and fabric to buy for any quilt size.
- No. 09Quilt BackingBacking yardage, comparing seam directions and wide-back.
- No. 10Circle SkirtWaist and hem radius, plus fabric for your width.
AI text tools
Browse 5 tools- No. 11Invisible Character RemoverFind and remove zero-width and non-breaking spaces.
- No. 12Transcript CleanerStrip timestamps and tags, and join lines into paragraphs.
- No. 13Context WindowEstimate tokens and pages against AI context limits.
- No. 14Markdown Table to ExcelTurn AI chat tables into Excel, CSV or clean cells.
- No. 15AI Image Aspect RatioPixel sizes, --ar settings and social media sizes.
How every tool is built
- 01
You see the arithmetic
Every answer lists the steps that produced it, so you can redo the sum on paper.
- 02
Nothing leaves your device
Calculations run in your browser. We never receive the numbers or text you enter.
- 03
Figures have a source and a date
Rates link to the official page they came from, with the day we last checked it.
Latest rate and rule updates
What changed on the site, and why.
- Resident credits confirmed for all six Ohio citiesAkron, Cleveland, Columbus, Dayton and Toledo give a 100% credit for tax paid to another city, capped at 2.5%; Youngstown caps it at 2.75%. The calculator now fills these in automatically.
- Toledo rate corrected to 2.5%Toledo’s income tax has been 2.5% since January 1, 2021. Some third-party sites still list 2.25%; we corrected our figure against the city’s own guidance.
- Michigan personal exemption updated to $5,900Michigan’s personal exemption rose from $5,800 in 2025 to $5,900 for 2026. Detroit’s city exemption stays at $600.
Recent guides
Practical answers to the questions behind each calculator.
- Are Invisible Characters an AI Watermark? Myths vs Facts
- DC Income Tax Brackets Explained With Real Paycheck Examples (2026)
- Deep Pour vs Tabletop Epoxy: Which to Use and How Thick to Pour
- Detroit City Income Tax: Who Has to Pay and How Much
- Epoxy Mix Ratios: Measuring by Volume vs Weight
- How Many Pages Can ChatGPT, Claude and Gemini Read?