➗ 分数转小数计算器（含循环小数）Fraction to Decimal Calculator (with Repeating Decimals)
把分数或带分数（如 3/8、1 2/7、−5/6）转换为小数，自动识别循环节并用括号标出，例如 1/7 = 0.(142857)，同时给出四舍五入的近似值。Convert a fraction or mixed number such as 3/8, 1 2/7 or −5/6 to a decimal, detecting the repeating block and showing it in brackets — 1/7 = 0.(142857) — plus a rounded value.
使用说明与常见问题How-to & FAQ
「分数转小数计算器（含循环小数）」是什么？What is the Fraction to Decimal Calculator (with Repeating Decimals) tool?
把分数或带分数（如 3/8、1 2/7、−5/6）转换为小数，自动识别循环节并用括号标出，例如 1/7 = 0.(142857)，同时给出四舍五入的近似值。Convert a fraction or mixed number such as 3/8, 1 2/7 or −5/6 to a decimal, detecting the repeating block and showing it in brackets — 1/7 = 0.(142857) — plus a rounded value.
如何使用「分数转小数计算器（含循环小数）」？How do I use the Fraction to Decimal Calculator (with Repeating Decimals) tool?
在「分数转小数计算器（含循环小数）」中，填写「分数」、「近似保留小数位」等参数，结果会随输入实时计算并显示在下方。In the Fraction to Decimal Calculator (with Repeating Decimals): Fill in "Fraction", "Rounded decimal places"; results are recalculated instantly as you type.
怎么判断是不是循环小数？How do I know if it repeats?
最简分数的分母只含质因数 2 和 5 时是有限小数，否则一定是循环小数。工具用长除法记录余数，余数重复时循环开始。A fraction in lowest terms terminates only if its denominator has no prime factors other than 2 and 5; otherwise it repeats. The tool does long division and spots the first repeated remainder.
括号是什么意思？What do the brackets mean?
括号内是循环节，例如 0.1(6) = 0.1666…，1.(285714) = 1.285714285714…The digits in brackets repeat forever: 0.1(6) = 0.1666…, 1.(285714) = 1.285714285714…
计算精度如何？How precise are the results?
「分数转小数计算器（含循环小数）」使用 JavaScript 双精度浮点数（约 15–16 位有效数字），部分功能使用 BigInt 处理大整数。The Fraction to Decimal Calculator (with Repeating Decimals) uses double-precision floating point (about 15–16 significant digits); some features use BigInt for large integers.
「分数转小数计算器（含循环小数）」免费吗？需要注册吗？Is the Fraction to Decimal Calculator (with Repeating Decimals) free? Do I need an account?
「分数转小数计算器（含循环小数）」完全免费，无需注册或安装，打开网页即可使用，手机和电脑都能用；输入的内容只在你的浏览器本地处理。The Fraction to Decimal Calculator (with Repeating Decimals) is completely free with no sign-up or install and works on phones and desktops; what you enter is processed only in your browser.