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Factorial Calculator

Math Calculators

n! — factorials including large numbers

Quick Answer

Factorial Calculator: n! — factorials including large numbers. Factorial Calculator uses standard math formulas to compute accurate results instantly.

10! =

3628800

7 digits · 2 trailing zeros

10!! (double)3840
A(10,5)30240
C(10,5)252
Trailing zeros2

How trailing zeros are counted

  1. 1A trailing zero = a factor pair 2×5; in n! the 5s are the bottleneck
  2. 2⌊10/5⌋ + ⌊10/25⌋ + ⌊10/125⌋ + … = 2
  3. 3Stirling: digits of n! ≈ 0.5·log₁₀(2πn) + n·log₁₀(n/e) → 7 digits

Factorial reference table

0!1
1!1
2!2
3!6
4!24
5!120
6!720
7!5,040
8!40,320
9!362,880
10!3,628,800
11!39,916,800
12!479,001,600
13!6,227,020,800
14!87,178,291,200
15!1,307,674,368,000
20!2,432,902,008,176,640,000
25!1.5511×10²⁵
50!3.0414×10⁶⁴
100!9.3326×10¹⁵⁷

💡 Factorials grow faster than exponentials: 70! ≈ 1.2×10¹⁰⁰ exceeds a googol, and the number of ways to shuffle 52 cards (52! ≈ 8×10⁶⁷) is more than atoms on Earth — every fair shuffle makes history.

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How to Use

  1. Enter values or expressions: type directly into the Factorial Calculator — keyboard friendly.
  2. Instant results: everything computes live as you type, no button needed.
  3. Follow the steps: the result panel shows full working and formula substitution.
  4. Copy or recompute: one-click copy; change any input to recalculate instantly.

Key Points

  • Factorial Calculator is a free online math tool — open and use, no sign-up.
  • All calculations run locally in your browser; your data never leaves the device.
  • Key capability: n! — factorials including large numbers.
  • Results come with formulas and reference tables so you can verify every number.

Formula & How It Works

Factorial Calculator formula

Factorial Calculator uses standard math formulas to compute accurate results instantly.

FAQ

How do I use the Factorial Calculator?
Open the page and fill in the input fields — results update automatically. n! — factorials including large numbers.
Are the results accurate?
Yes. All calculations use standard mathematical formulas and are verified for accuracy.
Is it free? Do I need to sign up?
Completely free. No registration, login or download required — just open and use.
Does it work on mobile?
Yes. The responsive design works on phones, tablets and desktops.
Is my data saved?
No. All calculations run locally in your browser. Nothing is uploaded or stored.

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Source & Updates

Standard mathematical formulas. All logic verified. Last updated: 2025-07

Last updated:

Formulas and content on this page are reviewed by the YiJianSuan team. For reference only — official sources prevail.

Maintained and periodically reviewed by the YiJianSuan editorial team — review process in ourEditorial Policy.

Cite this page: YiJianSuan. Factorial Calculator[EB/OL]. https://www.yijiansuan.com/en/c/math/factorial

Results provided by this tool are for reference only and do not constitute professional advice.