Bless Spell and how it works for multi attacks

https://www.dndbeyond.com/spells/2618933-bless

Whenever a target makes an attack roll or a saving throw before the spell ends, the target adds 1d4 to the attack roll or save.

If I can multi attack.  I roll both the 1d4 and the 1d20 for each and every attack.

Yes.

Quote from Character77006 >>

https://www.dndbeyond.com/spells/2618933-bless

Whenever a target makes an attack roll or a saving throw before the spell ends, the target adds 1d4 to the attack roll or save.

 

If I can multi attack.  I roll both the 1d4 and the 1d20 for each and every attack.

"Whenever" means "whenever". If it were limited to once per turn, it would say "Once per turn, when a target makes an attack roll..."

I think the question was more "Do I roll the d4 once for all attacks or for every attack?"

Quote from Natrel >>

I think the question was more "Do I roll the d4 once for all attacks or for every attack?"

 That would make sense. I think it’s a separate 1d4 roll for every d20 roll. I’m sure if a single d4 roll for the whole spell were intended, it would have said so explicitly. E.g., “ Roll 1d4. For the duration of the spell, each target of the spell can add the result of that roll to any attack roll or saving roll they make.”

Quote from ThelenyiWhinlaw >>

Quote from Natrel >>

I think the question was more "Do I roll the d4 once for all attacks or for every attack?"

 That would make sense. I think it’s a separate 1d4 roll for every d20 roll. I’m sure if a single d4 roll for the whole spell were intended, it would have said so explicitly. E.g., “ Roll 1d4. For the duration of the spell, each target of the spell can add the result of that roll to any attack roll or saving roll they make.”

Correct.