Help Center
X-Calculator Help
Everything happens on your device — X-Calculator has no servers, no account and no network access. This page covers each mode and the most common questions.
Getting started
Switch modes
Tap the mode pill at the top left (it shows the current mode, e.g. “Simple”) to switch between the eight modes. Your current value carries over between Simple and Scientific. Set your startup mode in Settings → Default mode.
Type or tap
Use the keypad, or a hardware keyboard on iPad — digits, + − × ÷, parentheses, %, ^, ! all work; Return is “=”, Esc clears, Backspace deletes. Undo and redo buttons sit above the keypad.
Save and share
Results can be copied, shared, or saved to History (⋯ menu). Structured calculators have Save to history and Share buttons under the result.
The modes
Simple
Everyday arithmetic with percentage semantics you expect (200 + 10% = 220), memory keys (MC/MR/M+/M−/MS) and a live result preview as you type.
Scientific
Trig (sin/cos/tan and inverses via 2nd), logarithms, powers, roots, factorial, constants (π, e, φ). The DEG key cycles degrees / radians / gradians — the active unit shows above the display. Domain errors (like ln(0)) are named, never NaN.
Engineering
Nine solve-for-the-unknown forms in SI units: Ohm's law, electrical power, series/parallel resistance, frequency ↔ wavelength, force, pressure, energy, torque and fluid flow. Pick the quantity to solve for; enter the others.
Financial
15 calculators across Loans, Investments, Interest, Retirement, Cash Flow and Everyday. EMI includes a full amortisation schedule with CSV and PDF export. Every result lists its assumptions — compounding, payment timing, rounding, day-count.
Programmer
Work in BIN, OCT, DEC and HEX with bitwise AND/OR/XOR/NOT and shifts. Tap a base row to switch input base; all bases update live.
Statistics
Paste or type a data list (commas, spaces or new lines) and get count, sum, mean, median, mode, min/max, range, quartiles, variance and standard deviation instantly.
Date & Time
Difference between dates (calendar and business days), add or subtract periods, and time arithmetic.
Conversion
Convert units of length, mass, temperature, volume, speed and more. Type a value and pick both units; the result updates live.
Common questions
Why does my bank's EMI differ slightly?
Institutions round differently and may use other day-count or timing conventions. Check the Assumptions section under every result — values marked “approx.” depend on those conventions. For actual transactions, the lender's figure prevails.
How do I change currency, precision or rounding?
Settings (⋯ menu → Settings): currency, decimal precision, number notation (plain / scientific / engineering / SI), rounding method and angle unit. Financial calculators can override compounding and payment frequency per calculation.
Where is my data stored?
On your device, only. History can be turned off, cleared, or exported as JSON from Settings. “Delete all data” removes everything and resets settings.
How do I report a problem?
Settings → Support → Report a bug. Fill in what happened and tap Send — it opens an email to us, with optional diagnostics you can review before sending. Or write directly to support@aidigiapps.com.