diff --git a/hideout-core/src/main/kotlin/dev/usbharu/hideout/core/infrastructure/exposedrepository/InstanceRepositoryImpl.kt b/hideout-core/src/main/kotlin/dev/usbharu/hideout/core/infrastructure/exposedrepository/InstanceRepositoryImpl.kt
index c7259dbb..09c2b9be 100644
--- a/hideout-core/src/main/kotlin/dev/usbharu/hideout/core/infrastructure/exposedrepository/InstanceRepositoryImpl.kt
+++ b/hideout-core/src/main/kotlin/dev/usbharu/hideout/core/infrastructure/exposedrepository/InstanceRepositoryImpl.kt
@@ -17,6 +17,7 @@
 package dev.usbharu.hideout.core.infrastructure.exposedrepository
 
 import dev.usbharu.hideout.core.domain.model.instance.*
+import dev.usbharu.hideout.core.infrastructure.exposed.uri
 import org.jetbrains.exposed.sql.*
 import org.jetbrains.exposed.sql.SqlExpressionBuilder.eq
 import org.jetbrains.exposed.sql.javatime.timestamp
@@ -37,9 +38,9 @@ class InstanceRepositoryImpl : InstanceRepository,
             it[id] = instance.id.instanceId
             it[name] = instance.name.name
             it[description] = instance.description.description
-            it[url] = instance.url.toString()
-            it[iconUrl] = instance.iconUrl.toString()
-            it[sharedInbox] = instance.sharedInbox?.toString()
+            it[url] = instance.url
+            it[iconUrl] = instance.iconUrl
+            it[sharedInbox] = instance.sharedInbox
             it[software] = instance.software.software
             it[version] = instance.version.version
             it[isBlocked] = instance.isBlocked
@@ -61,7 +62,7 @@ class InstanceRepositoryImpl : InstanceRepository,
     }
 
     override suspend fun findByUrl(url: URI): dev.usbharu.hideout.core.domain.model.instance.Instance? = query {
-        return@query Instance.selectAll().where { Instance.url eq url.toString() }.limit(1).singleOrNull()?.toInstance()
+        return@query Instance.selectAll().where { Instance.url eq url }.limit(1).singleOrNull()?.toInstance()
     }
 
     companion object {
@@ -74,9 +75,9 @@ fun ResultRow.toInstance(): InstanceEntity {
         id = InstanceId(this[Instance.id]),
         name = InstanceName(this[Instance.name]),
         description = InstanceDescription(this[Instance.description]),
-        url = URI.create(this[Instance.url]),
-        iconUrl = URI.create(this[Instance.iconUrl]),
-        sharedInbox = this[Instance.sharedInbox]?.let { URI.create(it) },
+        url = this[Instance.url],
+        iconUrl = this[Instance.iconUrl],
+        sharedInbox = this[Instance.sharedInbox],
         software = InstanceSoftware(this[Instance.software]),
         version = InstanceVersion(this[Instance.version]),
         isBlocked = this[Instance.isBlocked],
@@ -90,9 +91,9 @@ object Instance : Table("instance") {
     val id = long("id")
     val name = varchar("name", 1000)
     val description = varchar("description", 5000)
-    val url = varchar("url", 255).uniqueIndex()
-    val iconUrl = varchar("icon_url", 255)
-    val sharedInbox = varchar("shared_inbox", 255).nullable().uniqueIndex()
+    val url = uri("url", 255).uniqueIndex()
+    val iconUrl = uri("icon_url", 255)
+    val sharedInbox = uri("shared_inbox", 255).nullable().uniqueIndex()
     val software = varchar("software", 255)
     val version = varchar("version", 255)
     val isBlocked = bool("is_blocked")
diff --git a/hideout-core/src/test/kotlin/dev/usbharu/hideout/core/infrastructure/exposedrepository/InstanceRepositoryImplTest.kt b/hideout-core/src/test/kotlin/dev/usbharu/hideout/core/infrastructure/exposedrepository/InstanceRepositoryImplTest.kt
index ec30240f..6bcb52fb 100644
--- a/hideout-core/src/test/kotlin/dev/usbharu/hideout/core/infrastructure/exposedrepository/InstanceRepositoryImplTest.kt
+++ b/hideout-core/src/test/kotlin/dev/usbharu/hideout/core/infrastructure/exposedrepository/InstanceRepositoryImplTest.kt
@@ -44,8 +44,9 @@ class InstanceRepositoryImplTest : AbstractRepositoryTest(InstanceTable) {
 
         val table = assertTable
         assertThat(table).row(1).isEqualTo(InstanceTable.id, 1).isEqualTo(InstanceTable.name, "test")
-            .isEqualTo(InstanceTable.url, "https://www.example.com")
-            .isEqualTo(InstanceTable.iconUrl, "https://www.example.com").isEqualTo(InstanceTable.sharedInbox, null)
+            .value(InstanceTable.url).isEqualTo("https://www.example.com")
+            .value(InstanceTable.iconUrl).isEqualTo("https://www.example.com")
+            .isEqualTo(InstanceTable.sharedInbox, null)
             .isEqualTo(InstanceTable.software, "").isEqualTo(InstanceTable.version, "")
             .isEqualTo(InstanceTable.isBlocked, false).isEqualTo(InstanceTable.isMuted, false)
             .isEqualTo(InstanceTable.moderationNote, "").value(InstanceTable.createdAt)
@@ -96,8 +97,9 @@ class InstanceRepositoryImplTest : AbstractRepositoryTest(InstanceTable) {
 
         val table = assertTable
         assertThat(table).row(1).isEqualTo(InstanceTable.id, 1).isEqualTo(InstanceTable.name, "test")
-            .isEqualTo(InstanceTable.url, "https://www.example.com")
-            .isEqualTo(InstanceTable.iconUrl, "https://www.example.com").isEqualTo(InstanceTable.sharedInbox, null)
+            .value(InstanceTable.url).isEqualTo("https://www.example.com")
+            .value(InstanceTable.iconUrl).isEqualTo("https://www.example.com")
+            .isEqualTo(InstanceTable.sharedInbox, null)
             .isEqualTo(InstanceTable.software, "").isEqualTo(InstanceTable.version, "")
             .isEqualTo(InstanceTable.isBlocked, false).isEqualTo(InstanceTable.isMuted, false)
             .isEqualTo(InstanceTable.moderationNote, "").value(InstanceTable.createdAt)