diff --git a/server/app/com/xsn/explorer/services/BlockService.scala b/server/app/com/xsn/explorer/services/BlockService.scala
index 6812651..3748a1d 100644
--- a/server/app/com/xsn/explorer/services/BlockService.scala
+++ b/server/app/com/xsn/explorer/services/BlockService.scala
@@ -7,16 +7,17 @@ import com.alexitc.playsonify.models.pagination.{Limit, Offset, PaginatedQuery}
 import com.alexitc.playsonify.validators.PaginatedQueryValidator
 import com.xsn.explorer.cache.BlockHeaderCache
 import com.xsn.explorer.data.async.BlockFutureDataHandler
-import com.xsn.explorer.errors.{BlockRewardsNotFoundError, BlockhashFormatError}
+import com.xsn.explorer.errors.BlockRewardsNotFoundError
 import com.xsn.explorer.models._
 import com.xsn.explorer.models.persisted.BlockHeader
 import com.xsn.explorer.models.rpc.{Block, TransactionVIN}
 import com.xsn.explorer.models.values.{Blockhash, Height}
 import com.xsn.explorer.parsers.OrderingConditionParser
 import com.xsn.explorer.services.logic.{BlockLogic, TransactionLogic}
+import com.xsn.explorer.services.validators.BlockhashValidator
 import com.xsn.explorer.util.Extensions.FutureOrExt
 import javax.inject.Inject
-import org.scalactic.{Bad, Good, One, Or}
+import org.scalactic.{Bad, Good}
 import play.api.libs.json.{JsValue, Writes}
 
 import scala.concurrent.{ExecutionContext, Future}
@@ -25,6 +26,7 @@ class BlockService @Inject() (
     xsnService: XSNService,
     blockDataHandler: BlockFutureDataHandler,
     paginatedQueryValidator: PaginatedQueryValidator,
+    blockhashValidator: BlockhashValidator,
     blockLogic: BlockLogic,
     transactionLogic: TransactionLogic,
     orderingConditionParser: OrderingConditionParser,
@@ -40,13 +42,10 @@ class BlockService @Inject() (
       implicit writes: Writes[BlockHeader]): FutureApplicationResult[JsValue] = {
 
     val result = for {
-      lastSeenHash <- {
-        lastSeenHashString
-            .map(Blockhash.from)
-            .map { txid => Or.from(txid, One(BlockhashFormatError)).map(Option.apply) }
-            .getOrElse(Good(Option.empty))
-            .toFutureOr
-      }
+      lastSeenHash <- lastSeenHashString
+          .map { string => blockhashValidator.validate(string).map(Option.apply) }
+          .getOrElse(Good(None))
+          .toFutureOr
 
       _ <- paginatedQueryValidator.validate(PaginatedQuery(Offset(0), limit), maxHeadersPerQuery).toFutureOr
       orderingCondition <- orderingConditionParser.parseReuslt(orderingConditionString).toFutureOr
@@ -75,10 +74,7 @@ class BlockService @Inject() (
 
   def getRawBlock(blockhashString: String): FutureApplicationResult[JsValue] = {
     val result = for {
-      blockhash <- blockLogic
-          .getBlockhash(blockhashString)
-          .toFutureOr
-
+      blockhash <- blockhashValidator.validate(blockhashString).toFutureOr
       block <- xsnService.getRawBlock(blockhash).toFutureOr
     } yield block
 
@@ -96,10 +92,7 @@ class BlockService @Inject() (
 
   def getDetails(blockhashString: String): FutureApplicationResult[BlockDetails] = {
     val result = for {
-      blockhash <- blockLogic
-          .getBlockhash(blockhashString)
-          .toFutureOr
-
+      blockhash <- blockhashValidator.validate(blockhashString).toFutureOr
       details <- getDetailsPrivate(blockhash).toFutureOr
     } yield details
 
diff --git a/server/app/com/xsn/explorer/services/logic/BlockLogic.scala b/server/app/com/xsn/explorer/services/logic/BlockLogic.scala
index 1289c60..449c0bd 100644
--- a/server/app/com/xsn/explorer/services/logic/BlockLogic.scala
+++ b/server/app/com/xsn/explorer/services/logic/BlockLogic.scala
@@ -1,19 +1,14 @@
 package com.xsn.explorer.services.logic
 
 import com.alexitc.playsonify.core.ApplicationResult
-import com.xsn.explorer.errors.{BlockNotFoundError, BlockhashFormatError, TransactionNotFoundError}
+import com.xsn.explorer.errors.{BlockNotFoundError, TransactionNotFoundError}
 import com.xsn.explorer.models._
 import com.xsn.explorer.models.rpc.{Block, Transaction}
-import com.xsn.explorer.models.values.{Address, Blockhash, TransactionId}
+import com.xsn.explorer.models.values.{Address, TransactionId}
 import org.scalactic.{Bad, Good, One, Or}
 
 class BlockLogic {
 
-  def getBlockhash(string: String): ApplicationResult[Blockhash] = {
-    val maybe = Blockhash.from(string)
-    Or.from(maybe, One(BlockhashFormatError))
-  }
-
   def getPoWTransactionId(block: Block): ApplicationResult[TransactionId] = {
     val maybe = block.transactions.headOption
 
diff --git a/server/app/com/xsn/explorer/services/validators/BlockhashValidator.scala b/server/app/com/xsn/explorer/services/validators/BlockhashValidator.scala
new file mode 100644
index 0000000..d957a3a
--- /dev/null
+++ b/server/app/com/xsn/explorer/services/validators/BlockhashValidator.scala
@@ -0,0 +1,12 @@
+package com.xsn.explorer.services.validators
+
+import com.alexitc.playsonify.core.ApplicationResult
+import com.xsn.explorer.errors.BlockhashFormatError
+import com.xsn.explorer.models.values.Blockhash
+
+class BlockhashValidator {
+
+  def validate(string: String): ApplicationResult[Blockhash] = {
+    optional(string, BlockhashFormatError)(Blockhash.from)
+  }
+}
diff --git a/server/app/com/xsn/explorer/services/validators/package.scala b/server/app/com/xsn/explorer/services/validators/package.scala
new file mode 100644
index 0000000..1af28ee
--- /dev/null
+++ b/server/app/com/xsn/explorer/services/validators/package.scala
@@ -0,0 +1,13 @@
+package com.xsn.explorer.services
+
+import com.alexitc.playsonify.core.ApplicationResult
+import com.alexitc.playsonify.models.ApplicationError
+import org.scalactic.{One, Or}
+
+package object validators {
+
+  def optional[T](string: String, error: ApplicationError)(builder: String => Option[T]): ApplicationResult[T] = {
+    val maybe = builder(string)
+    Or.from(maybe, One(error))
+  }
+}
diff --git a/server/test/com/xsn/explorer/services/LedgerSynchronizerServiceSpec.scala b/server/test/com/xsn/explorer/services/LedgerSynchronizerServiceSpec.scala
index 880f4af..8f54dc8 100644
--- a/server/test/com/xsn/explorer/services/LedgerSynchronizerServiceSpec.scala
+++ b/server/test/com/xsn/explorer/services/LedgerSynchronizerServiceSpec.scala
@@ -13,7 +13,7 @@ import com.xsn.explorer.models.rpc.Block
 import com.xsn.explorer.models.values.{Blockhash, Height}
 import com.xsn.explorer.parsers.{OrderingConditionParser, TransactionOrderingParser}
 import com.xsn.explorer.services.logic.{BlockLogic, TransactionLogic}
-import com.xsn.explorer.services.validators.AddressValidator
+import com.xsn.explorer.services.validators.{AddressValidator, BlockhashValidator}
 import org.scalactic.{Bad, Good, One, Or}
 import org.scalatest.BeforeAndAfter
 import org.scalatest.concurrent.ScalaFutures
@@ -223,6 +223,7 @@ class LedgerSynchronizerServiceSpec extends PostgresDataHandlerSpec with BeforeA
       xsnService,
       new BlockFutureDataHandler(blockDataHandler)(Executors.databaseEC),
       new PaginatedQueryValidator,
+      new BlockhashValidator,
       new BlockLogic,
       new TransactionLogic,
       new OrderingConditionParser,