pray-calc

The main PrayCalc prayer times engine. Built on NREL SPA for solar position, covering all 14 major calculation methods and a physics-grounded dynamic angle mode.

Overview

pray-calc computes the six daily Islamic prayer times (Fajr, Sunrise, Dhuhr, Asr, Maghrib, Isha) for any location on Earth, any date, and any standard calculation method.

14 standard methods (ISNA, MWL, Egypt, Umm al-Qura, Tehran, Karachi, and more)
Dynamic angle mode (DPC) for physics-grounded Fajr and Isha
Asr: Shafi'i (shadow = 1×) and Hanafi (shadow = 2×)
High latitude fallback rules (1/7 night, angle-based, nearest day)
TypeScript-first, full type exports
ESM + CommonJS builds
Zero runtime dependencies (NREL SPA bundled)

GitHub: github.com/acamarata/pray-calc

Installation

<span><span style="color: var(--shiki-token-function)">pnpm</span><span style="color: var(--shiki-color-text)"> </span><span style="color: var(--shiki-token-string)">add</span><span style="color: var(--shiki-color-text)"> </span><span style="color: var(--shiki-token-string)">pray-calc</span></span>
<span></span>

Requires Node.js 20+.

getPrayerTimes

<span><span style="color: var(--shiki-token-function)">getPrayerTimes</span><span style="color: var(--shiki-color-text)">(options: PrayerTimesOptions): PrayerTimes</span></span>
<span></span>

Options

Parameter	Type	Required	Description
`date`	`Date`	Yes	Date to compute times for
`latitude`	`number`	Yes	Observer latitude in decimal degrees
`longitude`	`number`	Yes	Observer longitude in decimal degrees
`timezone`	`string`	Yes	IANA timezone string (e.g. `'America/New_York'`)
`method`	`CalculationMethod`	No	Calculation method (default: `'MWL'`)
`asrMethod`	`'shafii' \| 'hanafi'`	No	Asr shadow multiplier (default: `'shafii'`)
`elevation`	`number`	No	Metres above sea level (default: `0`)
`pressure`	`number`	No	Millibars (default: `1013.25`)
`temperature`	`number`	No	Celsius (default: `15`)
`highLatRule`	`HighLatRule`	No	Fallback for extreme latitudes

Returns

<span><span style="color: var(--shiki-color-text)">{</span></span>
<span><span style="color: var(--shiki-color-text)">  fajr</span><span style="color: var(--shiki-token-punctuation)">:</span><span style="color: var(--shiki-color-text)"> string        </span><span style="color: var(--shiki-token-comment)">// &quot;HH:MM&quot; in local time</span></span>
<span><span style="color: var(--shiki-color-text)">  sunrise</span><span style="color: var(--shiki-token-punctuation)">:</span><span style="color: var(--shiki-color-text)"> string</span></span>
<span><span style="color: var(--shiki-color-text)">  dhuhr</span><span style="color: var(--shiki-token-punctuation)">:</span><span style="color: var(--shiki-color-text)"> string</span></span>
<span><span style="color: var(--shiki-color-text)">  asr</span><span style="color: var(--shiki-token-punctuation)">:</span><span style="color: var(--shiki-color-text)"> string</span></span>
<span><span style="color: var(--shiki-color-text)">  maghrib</span><span style="color: var(--shiki-token-punctuation)">:</span><span style="color: var(--shiki-color-text)"> string</span></span>
<span><span style="color: var(--shiki-color-text)">  isha</span><span style="color: var(--shiki-token-punctuation)">:</span><span style="color: var(--shiki-color-text)"> string</span></span>
<span><span style="color: var(--shiki-color-text)">  midnight</span><span style="color: var(--shiki-token-punctuation)">:</span><span style="color: var(--shiki-color-text)"> string</span></span>
<span><span style="color: var(--shiki-color-text)">  date</span><span style="color: var(--shiki-token-punctuation)">:</span><span style="color: var(--shiki-color-text)"> string        </span><span style="color: var(--shiki-token-comment)">// ISO 8601 date</span></span>
<span><span style="color: var(--shiki-color-text)">  timezone</span><span style="color: var(--shiki-token-punctuation)">:</span><span style="color: var(--shiki-color-text)"> string</span></span>
<span><span style="color: var(--shiki-color-text)">  method</span><span style="color: var(--shiki-token-punctuation)">:</span><span style="color: var(--shiki-color-text)"> string</span></span>
<span><span style="color: var(--shiki-color-text)">}</span></span>
<span></span>

<span><span style="color: var(--shiki-token-keyword)">import</span><span style="color: var(--shiki-color-text)"> { getPrayerTimes } </span><span style="color: var(--shiki-token-keyword)">from</span><span style="color: var(--shiki-color-text)"> </span><span style="color: var(--shiki-token-string-expression)">&#39;pray-calc&#39;</span></span>
<span></span>
<span><span style="color: var(--shiki-token-keyword)">const</span><span style="color: var(--shiki-color-text)"> </span><span style="color: var(--shiki-token-constant)">times</span><span style="color: var(--shiki-color-text)"> </span><span style="color: var(--shiki-token-keyword)">=</span><span style="color: var(--shiki-color-text)"> </span><span style="color: var(--shiki-token-function)">getPrayerTimes</span><span style="color: var(--shiki-color-text)">({</span></span>
<span><span style="color: var(--shiki-color-text)">  date</span><span style="color: var(--shiki-token-keyword)">:</span><span style="color: var(--shiki-color-text)"> </span><span style="color: var(--shiki-token-keyword)">new</span><span style="color: var(--shiki-color-text)"> </span><span style="color: var(--shiki-token-function)">Date</span><span style="color: var(--shiki-color-text)">()</span><span style="color: var(--shiki-token-punctuation)">,</span></span>
<span><span style="color: var(--shiki-color-text)">  latitude</span><span style="color: var(--shiki-token-keyword)">:</span><span style="color: var(--shiki-color-text)"> </span><span style="color: var(--shiki-token-constant)">41.4993</span><span style="color: var(--shiki-token-punctuation)">,</span></span>
<span><span style="color: var(--shiki-color-text)">  longitude</span><span style="color: var(--shiki-token-keyword)">:</span><span style="color: var(--shiki-color-text)"> </span><span style="color: var(--shiki-token-keyword)">-</span><span style="color: var(--shiki-token-constant)">81.6944</span><span style="color: var(--shiki-token-punctuation)">,</span></span>
<span><span style="color: var(--shiki-color-text)">  timezone</span><span style="color: var(--shiki-token-keyword)">:</span><span style="color: var(--shiki-color-text)"> </span><span style="color: var(--shiki-token-string-expression)">&#39;America/New_York&#39;</span><span style="color: var(--shiki-token-punctuation)">,</span></span>
<span><span style="color: var(--shiki-color-text)">  method</span><span style="color: var(--shiki-token-keyword)">:</span><span style="color: var(--shiki-color-text)"> </span><span style="color: var(--shiki-token-string-expression)">&#39;ISNA&#39;</span><span style="color: var(--shiki-token-punctuation)">,</span></span>
<span><span style="color: var(--shiki-color-text)">})</span></span>
<span></span>
<span><span style="color: var(--shiki-token-constant)">console</span><span style="color: var(--shiki-token-function)">.log</span><span style="color: var(--shiki-color-text)">(times)</span></span>
<span><span style="color: var(--shiki-token-comment)">// {</span></span>
<span><span style="color: var(--shiki-token-comment)">//   fajr: &quot;05:34&quot;,</span></span>
<span><span style="color: var(--shiki-token-comment)">//   sunrise: &quot;06:52&quot;,</span></span>
<span><span style="color: var(--shiki-token-comment)">//   dhuhr: &quot;13:02&quot;,</span></span>
<span><span style="color: var(--shiki-token-comment)">//   asr: &quot;16:28&quot;,</span></span>
<span><span style="color: var(--shiki-token-comment)">//   maghrib: &quot;19:47&quot;,</span></span>
<span><span style="color: var(--shiki-token-comment)">//   isha: &quot;21:12&quot;,</span></span>
<span><span style="color: var(--shiki-token-comment)">//   ...</span></span>
<span><span style="color: var(--shiki-token-comment)">// }</span></span>
<span></span>

Methods

<span><span style="color: var(--shiki-token-keyword)">import</span><span style="color: var(--shiki-color-text)"> </span><span style="color: var(--shiki-token-keyword)">type</span><span style="color: var(--shiki-color-text)"> { CalculationMethod } </span><span style="color: var(--shiki-token-keyword)">from</span><span style="color: var(--shiki-color-text)"> </span><span style="color: var(--shiki-token-string-expression)">&#39;pray-calc&#39;</span></span>
<span></span>
<span><span style="color: var(--shiki-token-keyword)">const</span><span style="color: var(--shiki-color-text)"> </span><span style="color: var(--shiki-token-constant)">methods</span><span style="color: var(--shiki-token-keyword)">:</span><span style="color: var(--shiki-color-text)"> </span><span style="color: var(--shiki-token-function)">CalculationMethod</span><span style="color: var(--shiki-color-text)">[] </span><span style="color: var(--shiki-token-keyword)">=</span><span style="color: var(--shiki-color-text)"> [</span></span>
<span><span style="color: var(--shiki-color-text)">  </span><span style="color: var(--shiki-token-string-expression)">&#39;ISNA&#39;</span><span style="color: var(--shiki-token-punctuation)">,</span><span style="color: var(--shiki-color-text)">        </span><span style="color: var(--shiki-token-comment)">// 15°/15° — North America</span></span>
<span><span style="color: var(--shiki-color-text)">  </span><span style="color: var(--shiki-token-string-expression)">&#39;MWL&#39;</span><span style="color: var(--shiki-token-punctuation)">,</span><span style="color: var(--shiki-color-text)">         </span><span style="color: var(--shiki-token-comment)">// 18°/17° — Muslim World League</span></span>
<span><span style="color: var(--shiki-color-text)">  </span><span style="color: var(--shiki-token-string-expression)">&#39;EGYPT&#39;</span><span style="color: var(--shiki-token-punctuation)">,</span><span style="color: var(--shiki-color-text)">       </span><span style="color: var(--shiki-token-comment)">// 19.5°/17.5° — Egypt</span></span>
<span><span style="color: var(--shiki-color-text)">  </span><span style="color: var(--shiki-token-string-expression)">&#39;UMM_AL_QURA&#39;</span><span style="color: var(--shiki-token-punctuation)">,</span><span style="color: var(--shiki-color-text)"> </span><span style="color: var(--shiki-token-comment)">// 18°/90min — Saudi Arabia</span></span>
<span><span style="color: var(--shiki-color-text)">  </span><span style="color: var(--shiki-token-string-expression)">&#39;TEHRAN&#39;</span><span style="color: var(--shiki-token-punctuation)">,</span><span style="color: var(--shiki-color-text)">      </span><span style="color: var(--shiki-token-comment)">// 17.7°/14° — Iran</span></span>
<span><span style="color: var(--shiki-color-text)">  </span><span style="color: var(--shiki-token-string-expression)">&#39;KARACHI&#39;</span><span style="color: var(--shiki-token-punctuation)">,</span><span style="color: var(--shiki-color-text)">     </span><span style="color: var(--shiki-token-comment)">// 18°/18° — Pakistan</span></span>
<span><span style="color: var(--shiki-color-text)">  </span><span style="color: var(--shiki-token-string-expression)">&#39;KUWAIT&#39;</span><span style="color: var(--shiki-token-punctuation)">,</span><span style="color: var(--shiki-color-text)">      </span><span style="color: var(--shiki-token-comment)">// 18°/17.5° — Kuwait</span></span>
<span><span style="color: var(--shiki-color-text)">  </span><span style="color: var(--shiki-token-string-expression)">&#39;QATAR&#39;</span><span style="color: var(--shiki-token-punctuation)">,</span><span style="color: var(--shiki-color-text)">       </span><span style="color: var(--shiki-token-comment)">// 18°/90min — Qatar</span></span>
<span><span style="color: var(--shiki-color-text)">  </span><span style="color: var(--shiki-token-string-expression)">&#39;SINGAPORE&#39;</span><span style="color: var(--shiki-token-punctuation)">,</span><span style="color: var(--shiki-color-text)">   </span><span style="color: var(--shiki-token-comment)">// 20°/18° — Singapore</span></span>
<span><span style="color: var(--shiki-color-text)">  </span><span style="color: var(--shiki-token-string-expression)">&#39;FRANCE&#39;</span><span style="color: var(--shiki-token-punctuation)">,</span><span style="color: var(--shiki-color-text)">      </span><span style="color: var(--shiki-token-comment)">// 12°/12° — France</span></span>
<span><span style="color: var(--shiki-color-text)">  </span><span style="color: var(--shiki-token-string-expression)">&#39;RUSSIA&#39;</span><span style="color: var(--shiki-token-punctuation)">,</span><span style="color: var(--shiki-color-text)">      </span><span style="color: var(--shiki-token-comment)">// 16°/15° — Russia</span></span>
<span><span style="color: var(--shiki-color-text)">  </span><span style="color: var(--shiki-token-string-expression)">&#39;GULF&#39;</span><span style="color: var(--shiki-token-punctuation)">,</span><span style="color: var(--shiki-color-text)">        </span><span style="color: var(--shiki-token-comment)">// 19.5°/90min — Gulf states</span></span>
<span><span style="color: var(--shiki-color-text)">  </span><span style="color: var(--shiki-token-string-expression)">&#39;FCNA&#39;</span><span style="color: var(--shiki-token-punctuation)">,</span><span style="color: var(--shiki-color-text)">        </span><span style="color: var(--shiki-token-comment)">// 15°/15° — North America (Fiqh Council)</span></span>
<span><span style="color: var(--shiki-color-text)">  </span><span style="color: var(--shiki-token-string-expression)">&#39;JAKIM&#39;</span><span style="color: var(--shiki-token-punctuation)">,</span><span style="color: var(--shiki-color-text)">       </span><span style="color: var(--shiki-token-comment)">// 20°/18° — Malaysia</span></span>
<span><span style="color: var(--shiki-color-text)">  </span><span style="color: var(--shiki-token-string-expression)">&#39;DPC&#39;</span><span style="color: var(--shiki-token-punctuation)">,</span><span style="color: var(--shiki-color-text)">         </span><span style="color: var(--shiki-token-comment)">// Dynamic PrayCalc — physics-grounded</span></span>
<span><span style="color: var(--shiki-color-text)">]</span></span>
<span></span>

Dynamic mode

Use method: 'DPC' to enable dynamic angle computation. The algorithm adapts Fajr and Isha depression angles based on latitude, day of year, Earth-Sun distance, and elevation.

<span><span style="color: var(--shiki-token-keyword)">const</span><span style="color: var(--shiki-color-text)"> </span><span style="color: var(--shiki-token-constant)">times</span><span style="color: var(--shiki-color-text)"> </span><span style="color: var(--shiki-token-keyword)">=</span><span style="color: var(--shiki-color-text)"> </span><span style="color: var(--shiki-token-function)">getPrayerTimes</span><span style="color: var(--shiki-color-text)">({</span></span>
<span><span style="color: var(--shiki-color-text)">  date</span><span style="color: var(--shiki-token-keyword)">:</span><span style="color: var(--shiki-color-text)"> </span><span style="color: var(--shiki-token-keyword)">new</span><span style="color: var(--shiki-color-text)"> </span><span style="color: var(--shiki-token-function)">Date</span><span style="color: var(--shiki-color-text)">()</span><span style="color: var(--shiki-token-punctuation)">,</span></span>
<span><span style="color: var(--shiki-color-text)">  latitude</span><span style="color: var(--shiki-token-keyword)">:</span><span style="color: var(--shiki-color-text)"> </span><span style="color: var(--shiki-token-constant)">52.48</span><span style="color: var(--shiki-token-punctuation)">,</span></span>
<span><span style="color: var(--shiki-color-text)">  longitude</span><span style="color: var(--shiki-token-keyword)">:</span><span style="color: var(--shiki-color-text)"> </span><span style="color: var(--shiki-token-keyword)">-</span><span style="color: var(--shiki-token-constant)">1.90</span><span style="color: var(--shiki-token-punctuation)">,</span></span>
<span><span style="color: var(--shiki-color-text)">  timezone</span><span style="color: var(--shiki-token-keyword)">:</span><span style="color: var(--shiki-color-text)"> </span><span style="color: var(--shiki-token-string-expression)">&#39;Europe/London&#39;</span><span style="color: var(--shiki-token-punctuation)">,</span></span>
<span><span style="color: var(--shiki-color-text)">  method</span><span style="color: var(--shiki-token-keyword)">:</span><span style="color: var(--shiki-color-text)"> </span><span style="color: var(--shiki-token-string-expression)">&#39;DPC&#39;</span><span style="color: var(--shiki-token-punctuation)">,</span><span style="color: var(--shiki-color-text)">  </span><span style="color: var(--shiki-token-comment)">// dynamic angles</span></span>
<span><span style="color: var(--shiki-color-text)">})</span></span>
<span></span>

Dynamic mode is especially useful at latitudes above 45° or for applications where sky-accurate times are required. See Dynamic vs. Fixed Angles for the full explanation.

TypeScript types

<span><span style="color: var(--shiki-token-keyword)">import</span><span style="color: var(--shiki-color-text)"> </span><span style="color: var(--shiki-token-keyword)">type</span><span style="color: var(--shiki-color-text)"> {</span></span>
<span><span style="color: var(--shiki-color-text)">  PrayerTimesOptions</span><span style="color: var(--shiki-token-punctuation)">,</span></span>
<span><span style="color: var(--shiki-color-text)">  PrayerTimes</span><span style="color: var(--shiki-token-punctuation)">,</span></span>
<span><span style="color: var(--shiki-color-text)">  CalculationMethod</span><span style="color: var(--shiki-token-punctuation)">,</span></span>
<span><span style="color: var(--shiki-color-text)">  AsrMethod</span><span style="color: var(--shiki-token-punctuation)">,</span></span>
<span><span style="color: var(--shiki-color-text)">  HighLatRule</span><span style="color: var(--shiki-token-punctuation)">,</span></span>
<span><span style="color: var(--shiki-color-text)">} </span><span style="color: var(--shiki-token-keyword)">from</span><span style="color: var(--shiki-color-text)"> </span><span style="color: var(--shiki-token-string-expression)">&#39;pray-calc&#39;</span></span>
<span></span>
<span><span style="color: var(--shiki-token-keyword)">type</span><span style="color: var(--shiki-color-text)"> </span><span style="color: var(--shiki-token-function)">HighLatRule</span><span style="color: var(--shiki-color-text)"> </span><span style="color: var(--shiki-token-keyword)">=</span></span>
<span><span style="color: var(--shiki-color-text)">  </span><span style="color: var(--shiki-token-keyword)">|</span><span style="color: var(--shiki-color-text)"> </span><span style="color: var(--shiki-token-string-expression)">&#39;seventh-of-night&#39;</span><span style="color: var(--shiki-color-text)">   </span><span style="color: var(--shiki-token-comment)">// 1/7 of the night</span></span>
<span><span style="color: var(--shiki-color-text)">  </span><span style="color: var(--shiki-token-keyword)">|</span><span style="color: var(--shiki-color-text)"> </span><span style="color: var(--shiki-token-string-expression)">&#39;half-of-night&#39;</span><span style="color: var(--shiki-color-text)">      </span><span style="color: var(--shiki-token-comment)">// 1/2 of the night</span></span>
<span><span style="color: var(--shiki-color-text)">  </span><span style="color: var(--shiki-token-keyword)">|</span><span style="color: var(--shiki-color-text)"> </span><span style="color: var(--shiki-token-string-expression)">&#39;angle-based&#39;</span><span style="color: var(--shiki-color-text)">        </span><span style="color: var(--shiki-token-comment)">// reduced angle fallback</span></span>
<span><span style="color: var(--shiki-color-text)">  </span><span style="color: var(--shiki-token-keyword)">|</span><span style="color: var(--shiki-color-text)"> </span><span style="color: var(--shiki-token-string-expression)">&#39;nearest-day&#39;</span><span style="color: var(--shiki-color-text)">        </span><span style="color: var(--shiki-token-comment)">// nearest valid day</span></span>
<span></span>