Inverse Error Function Calculator
Free online inverse error function calculator. Enter your values and get instant results with the formula, step-by-step working, a worked example and FAQs — everything runs locally in your browser on Calcton, no signup required.
中文版：逆误差函数在线计算器
逆误差函数：给定 erf(y) = p，反解 y。erfinv(p) = √2·probit((1+p)/2)，蒙特卡洛反变换抽样与正态分位数的公共内核。
从概率回到分位数
标准正态分位数 Φ⁻¹(q) = √2 · erfinv(2q − 1)；如 Φ⁻¹(0.975) = √2 · erfinv(0.95) ≈ 1.959964
逆误差函数没有初等表达式，工程实现用 Winitzki 有理初值 + 牛顿迭代即可达机器精度。典型用途：把均匀随机数 u 映射成正态随机数 √2·erfinv(2u−1)（Box-Muller 的替代）、置信区间里查 z 值、信号处理中把 BER 换算成 Q 函数自变量。|p| → 1 时 erfinv 以 √(ln(1/ε)) 速度缓慢发散，双精度大约在 p = 1−10⁻¹⁵ 处失效。
How to use the Inverse Error Function Calculator
- Fill in the inputs with your own numbers — every field shows what it expects.
- The result updates instantly as you type; no "Calculate" click needed.
- Read the result card for the main figure, the step-by-step formula, and practical notes.
Frequently asked questions
Is the Inverse Error Function Calculator free?
Yes — all math calculators on Calcton are free, with no sign-up required. Your inputs are processed in your browser and never sent to a server.
Is there a Chinese version of this tool?
Yes. Use the Chinese version link above — it is the same calculator with the interface in Simplified Chinese.
References
Formulas and benchmarks used by this calculator follow these published sources.
KevinContent LeadCalcton Editorial Team · Last updated 2026-09-26
Kevin maintains Calcton's formula verification and content: every calculator cites the standard it implements, worked examples are recomputed programmatically, and health benchmarks follow WHO and international guidelines.
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