⚾ 投手防御率 ERA（支持 6.1 局写法）ERA Calculator (with 6.1 innings notation)
ERA = 自责分 × 9 ÷ 投球局数。局数可按棒球记分写法输入（6.1 = 6⅓ 局，6.2 = 6⅔ 局），也可选十进制局数；同时填写被安打和四坏球时还会算出 WHIP。本地处理。ERA = earned runs × 9 ÷ innings pitched. Innings can be entered in baseball notation (6.1 = 6⅓, 6.2 = 6⅔) or as decimal innings; fill in hits and walks to also get WHIP. Processed locally.
使用说明与常见问题How-to & FAQ
「投手防御率 ERA（支持 6.1 局写法）」是什么？What is the ERA Calculator (with 6.1 innings notation) tool?
ERA = 自责分 × 9 ÷ 投球局数。局数可按棒球记分写法输入（6.1 = 6⅓ 局，6.2 = 6⅔ 局），也可选十进制局数；同时填写被安打和四坏球时还会算出 WHIP。本地处理。ERA = earned runs × 9 ÷ innings pitched. Innings can be entered in baseball notation (6.1 = 6⅓, 6.2 = 6⅔) or as decimal innings; fill in hits and walks to also get WHIP. Processed locally.
如何使用「投手防御率 ERA」？How do I use the ERA Calculator (with 6.1 innings notation) tool?
填写自责分和投球局数，即可得到投手防御率 ERA = 自责分 × 9 ÷ 投球局数。结果会随输入实时更新。Enter the earned runs and innings pitched to get ERA = earned runs × 9 ÷ innings pitched. The result updates as you type.
6.1 局是什么意思？What does 6.1 innings mean?
棒球记分里小数点后是出局数：6.1 局 = 6 局又 1 个出局 = 6⅓ 局，6.2 局 = 6⅔ 局；.3 及以上无效（3 个出局就是下一局）。本页默认按这种写法换算，例如 2 个自责分、6.1 局的 ERA = 2 × 9 ÷ 6.333… = 2.84。如果你的数据是十进制局数（6.5 = 6½ 局），把「局数写法」改成十进制即可。In baseball box scores the digit after the point counts outs: 6.1 innings is 6 innings and one out, i.e. 6⅓, and 6.2 is 6⅔; .3 or more is invalid because three outs make the next inning. The page converts this notation by default, so 2 earned runs in 6.1 innings gives ERA = 2 × 9 ÷ 6.333… = 2.84. If your data uses decimal innings (6.5 = 6½), switch the notation to decimal.
WHIP 怎么算？How is WHIP calculated?
WHIP = (被安打 + 四坏球) ÷ 投球局数，表示每局平均让多少人上垒。两项都填写时才会显示。WHIP = (hits + walks) ÷ innings pitched, the average number of base runners allowed per inning. It is shown when both are filled in.
0 局可以吗？Can innings be 0?
不行。0 局时 ERA 没有定义（除以 0），页面会提示。No. ERA is undefined for 0 innings (division by zero), and the page says so.
能举个计算实例吗？Can you show a worked example?
例如在「投手防御率 ERA（支持 6.1 局写法）」中填 自责分 = 9，投球局数 = 27，局数写法 = 棒球写法（.1 = ⅓ 局，.2 = ⅔ 局），结果区显示：投球局数：27（81 个出局）；ERA：3.00For example, entering Earned runs = 9, Innings pitched = 27, Innings notation = Baseball notation (.1 = ⅓, .2… in the ERA Calculator (with 6.1 innings notation) gives: Innings pitched: 27 (81 outs); ERA: 3.00
哪些输入会被检查？Which inputs are validated?
「投手防御率 ERA（支持 6.1 局写法）」会检查这些输入——「自责分」：所选方式用到时必须填写；「被安打（可选，用于 WHIP）」、「四坏球（可选，用于 WHIP）」：可留空；绝对值超过 10¹⁵ 的数也会被拒绝。不符合时结果区显示具体提示，不会给出数字。The ERA Calculator (with 6.1 innings notation) checks its inputs — "Earned runs": required when the chosen option uses it; "Hits allowed (optional, for WHIP)", "Walks (optional, for WHIP)": optional; numbers above 10¹⁵ in absolute value are rejected too. When a value fails, the result area names the problem instead of showing a number.
有哪些选项可以调整？What options can I adjust?
「投手防御率 ERA（支持 6.1 局写法）」的设置：「自责分」默认 12；「投球局数」默认 40.1；「局数写法」可选 棒球写法（.1 = ⅓ 局，.2 = ⅔ 局）、十进制局数（6.5 = 6½ 局）（默认 棒球写法（.1 = ⅓ 局，.2 = ⅔ 局））；「被安打（可选，用于 WHIP）」可留空；「四坏球（可选，用于 WHIP）」可留空。每次生成结果都按当前设置处理。Settings in the ERA Calculator (with 6.1 innings notation) — "Earned runs" default 12; "Innings pitched" default 40.1; "Innings notation": Baseball notation (.1 = ⅓, .2 = ⅔), Decimal innings (6.5 = 6½) (default Baseball notation (.1 = ⅓, .2 = ⅔)); "Hits allowed (optional, for WHIP)" optional; "Walks (optional, for WHIP)" optional. The result always uses the current settings.
计算精度如何？How precise are the results?
「投手防御率 ERA（支持 6.1 局写法）」使用 JavaScript 双精度浮点数（约 15–16 位有效数字）；极大或极小的数值可能存在精度误差。The ERA Calculator (with 6.1 innings notation) uses double-precision floating point (about 15–16 significant digits); very large or very small values may lose precision.
「投手防御率 ERA（支持 6.1 局写法）」免费吗？需要注册吗？Is the ERA Calculator (with 6.1 innings notation) free? Do I need an account?
「投手防御率 ERA（支持 6.1 局写法）」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 ERA Calculator (with 6.1 innings notation) is completely free with no sign-up or install and works on phones and desktops; what you enter is processed only in your browser.