Herod swore to give Herodias's dancing daughter anything she asked, up to how much?

Answer: Half his kingdom

Herod swore, "Whatever you ask of me, I will give you, up to half my kingdom!"

“When the daughter of Herodias came and danced, she pleased Herod and his guests, and the king said to the girl, “Ask me for whatever you wish, and I will give it to you.” And he swore to her, “Whatever you ask of me, I will give you, up to half my kingdom!””— Mark 6:22-23 (BSB)