Harper sits next to 5 phonetic neighbors — Jasper, Parker, and Carter are the closest matches by sound. Most share Harper's English-origin cluster, so the rhythm and vowel shape carry across the list.
You searched for names like
"harp player, one who plays the harp"
"son of Otto, helpful"
"a natural watercourse"
"disciple of the dove"
"beloved, dear one"
"my help is God"
"canal worker, church official"
"from India"
"meadow of the gods"
"sun, sunshine"
"follower of Calvin (in Protestant tradition)"
"sky, heavens"
"steep hill meadow"
"of noble origin"
"modern invented name, unique spirit"
"skilled craftsman"
"airplane, aircraft"
"boar-friend, warrior companion"
"strong as an oak"
"woodland clearing used for hunting"
"crooked hill"
Similar sound: These names share phonetic patterns with Harper — similar vowel sounds, consonant clusters, or rhythm.
Shared roots: Several names on this list have Old English hearpere origins, giving them the same cultural heritage as Harper.
Rhythm: Harper is a 2-syllable name. Names with the same syllable count tend to feel interchangeable when you're narrowing your list.