Why Use a Simple Online Calculator?为什么需要极简在线计算器？
A clean, fast calculator in the browser is perfect for quick sums, tips, splits, or unit checks without opening an app or reaching for your phone. No ads, no signup, and no data sent to any server—everything runs in your browser so your privacy stays intact.在浏览器里使用一款干净、快速的计算器，适合做零散的加减乘除、小费分摊、单位核对等，无需打开应用或掏手机。无广告、免注册、数据不上传任何服务器，一切在本地运行，隐私自然得到保护。
When a Basic Calculator Is Enough何时基础计算器就够用
For daily tasks like splitting a bill, converting a quick percentage, or checking a receipt, a simple four-function calculator is often all you need. Scientific and graphing calculators are great for school or work, but they add complexity and sometimes track usage. A minimal calculator does one job well: fast, accurate arithmetic without distraction.日常场景里：分账、算百分比、核对小票等，四则运算往往就够用。科学计算器或图形计算器适合学业与专业工作，但会带来复杂度和可能的使用追踪。极简计算器只做一件事：快速、准确的四则运算，不被多余功能打扰。
A Short History of the Calculator计算器的简史
Mechanical adding machines and slide rules preceded the electronic calculator. The first handheld electronic calculators appeared in the 1970s and quickly replaced desktop mechanical units. Today, calculator apps and web tools are everywhere—but many come with ads, analytics, or account requirements. A privacy-first online calculator keeps the original promise: instant math with no strings attached.在电子计算器之前，人们使用机械加法器和计算尺。上世纪 70 年代出现第一批手持电子计算器，并迅速取代台式机械计算器。如今计算器应用和网页工具随处可见，但很多带有广告、统计或登录要求。以隐私为先的在线计算器则回归本质：即算即走，无需绑定任何东西。
Tips for Quick and Accurate Use快速准确使用的小技巧
Use the keyboard for numbers and operators (+, -, *, /) when possible; Enter runs the calculation and Escape clears. For long expressions, work in small steps to avoid errors. This tool supports decimals and negative numbers, so you can handle expenses, refunds, and simple conversions without leaving the page.尽量用键盘输入数字和运算符（+、-、*、/）；Enter 得出结果，Escape 清空。算式较长时，可以分步计算以减少出错。本工具支持小数与负数，可用来算开支、退款和简单换算，无需跳转其他页面。
Privacy and Why It Matters隐私为何重要
Many calculator apps and websites collect usage data or require an account. Here, every keystroke and result stays in your browser. Nothing is sent to a server, so there are no logs, no analytics, and no risk of your numbers being stored or shared. For bills, taxes, or personal budgets, that peace of mind is part of the value. Use this calculator whenever you need quick, honest math without strings attached.不少计算器应用或网站会收集使用数据或要求登录。本工具中，每一次按键与结果都只留在你的浏览器内，不会上传到服务器，因此没有日志、没有统计、也没有数据被保存或共享的风险。在算账单、税务或个人预算时，这份安心本身就是价值。当你需要快速、干净、无绑定的计算时，随时使用本工具即可。
Common Uses: Bills, Tips, and Percentages常见用途：账单、小费与百分比
A simple calculator is ideal for splitting a restaurant bill, adding a tip (e.g. 15% or 20%), or working out a discount. You can key in the total, multiply by 0.15 or 0.2 for the tip, then add to get the final amount. For discounts, multiply the price by the decimal form of the percentage you keep (e.g. 0.8 for 20% off). Parents and students use it for homework checks and quick arithmetic; small businesses use it for invoices and change. Because the tool supports decimals and negative numbers, you can also do refunds or adjustments without switching to another app.极简计算器非常适合分账、加小费（如 15% 或 20%）或算折扣。输入总价后乘以 0.15 或 0.2 得出小费，再加总即可。算折扣时用原价乘以保留比例的十进制（如打 8 折用 0.8）。家长和学生可用来核对作业和口算，小商家可用来算发票和找零。因支持小数与负数，也可用于退款或调账，无需另开应用。
Keyboard Shortcuts and Efficiency键盘快捷键与效率
To work faster, use the number keys and the operators +, -, *, / on your keyboard. Press Enter to evaluate the expression and Escape to clear the display. Backspace removes the last character. There is no need to click every button with the mouse—once you get used to the keys, you can run through a calculation in seconds. For long or nested expressions, break them into steps: calculate the inner part first, note the result, then use it in the next step. That reduces errors and keeps the logic clear.想提高效率，可用键盘数字键和 +、-、*、/ 输入，Enter 得出结果，Escape 清空，Backspace 删除最后一位。不必用鼠标逐个点击，熟悉后几秒即可算完。遇到较长或嵌套算式，可分步计算：先算内层、记下结果，再代入下一步，既减少出错也便于核对。
When to Choose a Scientific or Graphing Calculator何时改用科学或图形计算器
This tool is built for basic arithmetic: addition, subtraction, multiplication, division, decimals, and negative numbers. It does not handle square roots, powers, logarithms, trigonometry, or statistics. For school maths, science, or engineering, you may need a scientific calculator; for calculus or data visualisation, a graphing calculator or dedicated software is more appropriate. For everyday sums, tips, and quick checks, this minimal calculator is enough—and because it runs locally, you can use it even when offline or when you prefer not to send data to any service.本工具面向基础四则运算：加减乘除、小数与负数，不包含开方、幂、对数、三角函数或统计。若涉及中学数学、科学或工程，可能需要科学计算器；若涉及微积分或数据可视化，则适合用图形计算器或专业软件。日常算账、小费和快速核对，用这款极简计算器即可；且因完全本地运行，断网或不想把数据交给任何服务时也能照常使用。