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Math calculators that show the working
Six calculators that give you the answer and the steps that got there — the part most sites put behind a paywall. Free on the web, and in an app for when you are offline.
Quadratic Equation Solver
Step by step
- Start from the quadratic formulax = −b ± b2 − 4ac2a
- Substitute a, b and cx = −(−2) ± (−2)2 − 4(1)(−15)2(1)
- Work out the discriminant, b² − 4acΔ = (−2)2 − 4(1)(−15) = 64
- The discriminant is a perfect square, so the roots are rational64 = 8
- Take the plus branchx₁ = 2 + 82 = 5
- Take the minus branchx₂ = 2 − 82 = −3
Also worth knowing
- Vertex
- (1, −16)
- Axis of symmetry
- x = 1
- Discriminant
- 64
- Parabola opens
- upward
- Factored form
- (x − 5)(x + 3) = 0
The calculators
Pick the one you need
Every one of these runs free in your browser, shows its full working, and has a matching app for iPhone and Android.
Quadratic Equation Solver
Solve any quadratic equation and see every step of the work.
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Fraction Calculator
Add, subtract, multiply and divide fractions — with the working shown.
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Sarrus Rule Calculator
Find the determinant of any 3×3 matrix, with the diagonals drawn for you.
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Base Converter
Convert between any two number bases and see how the conversion works.
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Area Calculator
Area and perimeter for nine shapes, with the formula shown every time.
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Rule of Three Calculator
Solve any proportion by cross multiplication, direct or inverse.
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All in One Calculator
Six calculators in one app — no ads, works offline.
Open calculator →Why this site exists
The steps are the point
Nothing is gated
The full derivation is on the page, free, every time. No account, no trial, no “unlock steps” button.
Real notation
Fractions stack, radicals get an overbar, matrices get brackets — typeset as text, so you can copy it straight into your homework.
Built by one developer
One developer builds and maintains all seven apps. No ad networks, no trackers, no data collection on this site.
On your phone
The same calculators, offline
Each calculator has an app for iPhone and Android. They work with no signal, and add plain-English AI explanations and dark mode through the optional PRO subscription.
Quadratic Equation AI Solver
Free download · 9 guides
Fraction Calculator Smart Calc
Free download · 9 guides
Sarrus Calculator Matrix Det
Free download · 9 guides
Base Conversion AI Calculator
Free download · 9 guides
Area Calculator: AI Solver
Free download · 9 guides
Rule of 3: AI Calculator
Free download · 9 guides
All in One Calculator - Math
$1.99 · 6 guides
FAQ
About these calculators
Are these calculators really free?
Yes. Every calculator on this site runs free in your browser with no account, no daily limit and no step-by-step paywall. The full working is shown every time.
Do I need to install anything?
No. The calculators run in the browser on any phone, tablet or computer. The apps exist for when you want to work offline, but nothing here requires them.
Do the calculators show the steps, or just the answer?
Both. Every calculator shows the full derivation underneath the answer — the substitutions, the intermediate values and the reasoning — because the steps are usually the part you actually need.
What is the difference between the website and the apps?
The maths is identical and equally free. The apps add offline use, and an optional PRO subscription unlocks plain-English AI explanations and dark mode.
Does this site track me or show ads?
No. There are no ad networks, no analytics scripts and no third-party requests of any kind. Your calculations never leave your device.