🌌 光日 ↔ 一拃Light-day to Span
光日与一拃互算（1 light-d = 1.13307385701e+14 span）。本地换算，附常用相关单位。Convert light-day and span (1 light-d = 1.13307385701e+14 span). Runs locally with related units.
点击任意一行可复制该结果；小于 0.0001 或不小于 10¹⁵ 的数值用 × 10ⁿ 科学计数法显示Click any row to copy that result. Values below 0.0001 or at least 10¹⁵ are shown in × 10ⁿ notation
使用说明与常见问题How-to & FAQ
「光日 ↔ 一拃」是什么？What is the Light-day to Span tool?
光日与一拃互算（1 light-d = 1.13307385701e+14 span）。本地换算，附常用相关单位。Convert light-day and span (1 light-d = 1.13307385701e+14 span). Runs locally with related units.
如何使用「光日 ↔ 一拃」？How do I use the Light-day to Span tool?
在「光日 ↔ 一拃」中输入数值并选择原单位，表格会同时列出换算到所有其他单位的结果，可一键复制。Enter a value in the Light-day to Span and choose the source unit; the table shows the value in every other unit at once, ready to copy.
1 光日等于多少一拃？How many span in 1 light-day?
1 light-d = 1.13307385701e+14 span（按国际定义系数）。1 light-d = 1.13307385701e+14 span (international definition).
如何把光日换算成一拃？How do I convert light-day to span?
结果 = 数值 × 1.13307385701e+14。例如 8.82555001878e-15 light-d = 1 span。result = value × 1.13307385701e+14. Example: 8.82555001878e-15 light-d = 1 span.
光日/一拃属于哪类单位？What kind of units are light-day/span?
二者同属「长度」量纲，可安全互算；也可打开「length-converter」做多单位对照。Both are length units; see also the length converter hub.
换算系数准确吗？Are the conversion factors exact?
「光日 ↔ 一拃」采用国际单位制（SI）或公认标准中的定义值作为换算系数，结果保留约 10 位有效数字。The Light-day to Span uses factors defined by the SI or other recognised standards and shows about 10 significant digits.
「光日 ↔ 一拃」免费吗？需要注册吗？Is the Light-day to Span free? Do I need an account?
「光日 ↔ 一拃」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 Light-day to Span is completely free with no sign-up or install and works on phones and desktops; what you enter is processed only in your browser.