I'm surprised
Use this if you identify as female. Adjectives in Spanish must match the gender of the person.
A common exclamation meaning 'What a surprise!'. Use it right when you hear the surprising news.
Literally 'I wasn't expecting it'. Perfect for expressing that something was unforeseen.
A very common phrase meaning 'I can't believe it!'. Use it to show disbelief or shock.
Thank you for the party. I'm very surprised!
You arrived early. What a surprise!
My sister is getting married. I can't believe it!
Ana didn't come to the meeting. I wasn't expecting that.
'Estoy sorprendido/a' is the standard and understood everywhere. The alternatives are also widely used across Latin America.
In addition to the standard phrases, you will hear the very colloquial '¡qué fuerte!' or 'estoy flipando' to express surprise, especially among younger people.
Informal expressions like '¡No manches!' or '¡Órale!' are frequently used to react to surprising information.
You might hear 'Quedé helado' (for a male speaker) or 'Quedé helada' (for a female speaker), meaning 'I was frozen/shocked'.
Similar to Argentina, 'Quedé frío/a' ('I was left cold') is a common way to express being taken by surprise.
Using 'Soy sorprendido'. — Always use 'Estoy sorprendido'. Surprise is a temporary state or feeling (a condition), which requires the verb 'estar', not 'ser' (which is for permanent characteristics).
Forgetting gender agreement. — If you are female, you must say 'Estoy sorprendida' (ending in -a). If you are male, say 'Estoy sorprendido' (ending in -o). The adjective must match your gender.
Using 'sorpresa' as an adjective, like 'Estoy sorpresa'. — 'Sorpresa' is a noun meaning 'a surprise'. The adjective is 'sorprendido/a'. The correct phrase is 'Estoy sorprendido/a' or '¡Qué sorpresa!' (What a surprise!).