The German ä sounds like the "e" in English "bed" or "set". It's an open "eh" sound — easy for English speakers since you already make this sound every day!
Why does "a" change?
The two dots (umlaut) shift the sound forward in your mouth. Think of "a" as a wide-open "ah" and "ä" as a narrower "eh". You'll see ä a lot in plurals — for example, Mann (man) → Männer (men), Apfel (apple) → Äpfel (apples).
You already know this sound
English
bed
the "e" here = the ä sound
English
said
same "eh" sound, different spelling
English
red
another everyday "eh" sound
Hindi
pet (पेट)
"stomach" — same "eh" sound
Hear the difference: a → ä
Read both words aloud — listen how the "a" shifts to "eh" when the umlaut appears.