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Máy tính hoán vị và tổ hợp

Permutation and combination calculator: calculate P(n,r) and C(n,r) from total and pick count with formulas for math, with one-click copy and offline.

Cách sử dụng

Enter n and r and pick a type to calculate instantly.

Overview

Permutation & Combination Calculator is a math tool that Permutation and combination calculator: calculate P(n,r) and C(n,r) from total and pick count with formulas for math, with one-click copy and offline. It runs 100% in your browser with no upload, so you get instant results with privacy. Whether you need a quick answer or batch processing with precise control, you can enter, validate and export in seconds. The UI is responsive on mobile, tablet and desktop and supports one-click copy.

Use cases

  • Geometry solving
  • Combinatorics and EV
  • Mean/variance/probability
  • Base and scientific notation
  • Use it to cross-check “排列组合、排列数” in reports, docs or APIs to avoid manual conversion errors

How to use

  1. 1 Enter numbers and pick formula
  2. 2 See step-by-step derivation
  3. 3 Switch precision/display
  4. 4 Save frequent formulas

Highlights

  • Local & private: processing stays in your browser
  • Live validation with tolerant parsing
  • One-click copy and export for docs, code or sheets
  • Batch and offline support under poor network

Notes

  • Use high-precision mode for big numbers
  • Small samples fluctuate
  • Floating errors are denoised but verify extremes

FAQ

Fractions?
Type 3/4 to calculate as fraction.
Formulas reliable?
Standard formulas with sources shown.
How is Permutation & Combination Calculator different?
It runs locally with a focus on speed and privacy, plus tolerant parsing for “排列组合、排列数” and one-click copy for reuse.
Can I use results in official reports?
Use it as a working draft and cross-check with authoritative sources; keep the exported log and parameters for traceability.
Tip：Tip: Bookmark this page or pin the tab; find related tools via categories and search (convert → calculate → export).
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All calculations run locally in your browser; nothing is uploaded.