Is Using the Umm al-Qura Makkah Calendar Accurate for Sunni Hanafi Barelwi Prayer Timings?

Umm ul Qura Asr time is at mithl awwal not mithlayn.

 

Not sure about API. For any query, you will need to contact Majalis Tauqeet through "Prayer Time" application or at the link below.
https://departments.dawateislami.net/toqeet/contactus.php

https://www.dawateislami.net/downloads/islamic-apps/prayer-times-&-qibla
https://departments.dawateislami.net/toqeet/english.php
https://dawateislami.net/prayer-times/

At least for higher latitudes where prayer times become tricky to determine, DI's app work well. In UK, Mufti Shams-ul Huda Misbahi (who has been at the forefront of establishing common salah timetable/methodology across the UK masajids) has personally attested that DI prayer times are accurately determined.

I have also found Turkish Fazilet calendar (based on Hanafi rulings) to be in close agreement with DI's timetable.
https://faziletcalendar.com/

 

http://www.islamicacademy.org/html/Times/Mekkah_SA.htm

I've found this to be the most reliable.

 

Is they're providing any API for it?

 

You can use Dawat-e-Islami's prayer timetable (and app) as guidance. The timetable and calculation they follow is aligned with Hanafi methodology.

 

I am currently developing a website focused on providing accurate prayer timings, and the site is live now (Salatalert.com). For the time being, I am displaying the prayer times according to the Umm al-Qura Makkah calendar. I wanted to ask if this method of calculating prayer timings aligns with the Sunni Hanafi Barelwi school of thought? Are there any adjustments or other calculation methods recommended to ensure accuracy for Hanafi Barelwi followers living in Saudi Arabia?
JazakAllah Khair for your guidance.