diff --git a/it/src/test/scala/com/wavesplatform/it/sync/transactions/DataTransactionSuite.scala b/it/src/test/scala/com/wavesplatform/it/sync/transactions/DataTransactionSuite.scala
index 00d433a4a53..eed2331c28f 100644
--- a/it/src/test/scala/com/wavesplatform/it/sync/transactions/DataTransactionSuite.scala
+++ b/it/src/test/scala/com/wavesplatform/it/sync/transactions/DataTransactionSuite.scala
@@ -138,9 +138,9 @@ class DataTransactionSuite extends BaseTransactionSuite {
 
     sender.getData(secondAddress, "int") shouldBe intEntry2
     sender.getData(secondAddress, "bool") shouldBe boolEntry2
-    sender.getData(secondAddress, "blob").equals(blobEntry2)
-    sender.getData(secondAddress, "str").equals(stringEntry2)
-    sender.getData(secondAddress).equals(dataAllTypes)
+    sender.getData(secondAddress, "blob") shouldBe blobEntry2
+    sender.getData(secondAddress, "str") shouldBe stringEntry2
+    sender.getData(secondAddress) shouldBe dataAllTypes.sortBy(_.key)
 
     notMiner.assertBalances(secondAddress, balance2 - fee, eff2 - fee)
 
@@ -218,9 +218,6 @@ class DataTransactionSuite extends BaseTransactionSuite {
 
     assertBadRequestAndResponse(sender.postJson("/addresses/data", request(notValidBlobValue + ("value" -> JsString("base64:not a base64")))),
                                 "Illegal base64 character")
-
-    assertBadRequestAndResponse(sender.postJson("/addresses/data", request(notValidBlobValue + ("value" -> JsString("yomp")))),
-                                "base64:chars expected")
   }
 
   test("transaction requires a valid proof") {
diff --git a/lang/js/src/main/scala/com/wavesplatform/lang/Global.scala b/lang/js/src/main/scala/com/wavesplatform/lang/Global.scala
index 0d7f341ac60..fbebaf1790c 100644
--- a/lang/js/src/main/scala/com/wavesplatform/lang/Global.scala
+++ b/lang/js/src/main/scala/com/wavesplatform/lang/Global.scala
@@ -4,7 +4,10 @@ import com.wavesplatform.lang.v1.BaseGlobal
 
 object Global extends BaseGlobal {
   def base58Encode(input: Array[Byte]): Either[String, String] = impl.Global.base58Encode(input)
-  def base58Decode(input: String): Either[String, Array[Byte]] = impl.Global.base58Decode(input)
+  def base58Decode(input: String, limit: Int): Either[String, Array[Byte]] = impl.Global.base58Decode(input, limit)
+
+  def base64Encode(input: Array[Byte]): Either[String, String] = impl.Global.base64Encode(input)
+  def base64Decode(input: String, limit: Int): Either[String, Array[Byte]] = impl.Global.base64Decode(input, limit)
 
   def curve25519verify(message: Array[Byte], sig: Array[Byte], pub: Array[Byte]): Boolean = impl.Global.curve25519verify(message, sig, pub)
   def keccak256(message: Array[Byte]): Array[Byte]                                        = impl.Global.keccak256(message)
diff --git a/lang/js/src/main/scala/com/wavesplatform/lang/impl/Global.scala b/lang/js/src/main/scala/com/wavesplatform/lang/impl/Global.scala
index d14e596226f..9082e054aae 100644
--- a/lang/js/src/main/scala/com/wavesplatform/lang/impl/Global.scala
+++ b/lang/js/src/main/scala/com/wavesplatform/lang/impl/Global.scala
@@ -7,7 +7,10 @@ import scala.scalajs.{js => platform}
 @JSGlobalScope
 object Global extends platform.Object {
   def base58Encode(input: Array[Byte]): Either[String, String] = platform.native
-  def base58Decode(input: String): Either[String, Array[Byte]] = platform.native
+  def base58Decode(input: String, limit: Int): Either[String, Array[Byte]] = platform.native
+
+  def base64Encode(input: Array[Byte]): Either[String, String] = platform.native
+  def base64Decode(input: String, limit: Int): Either[String, Array[Byte]] = platform.native
 
   def curve25519verify(message: Array[Byte], sig: Array[Byte], pub: Array[Byte]): Boolean = platform.native
   def keccak256(message: Array[Byte]): Array[Byte]                                        = platform.native
diff --git a/lang/jvm/src/main/scala/com/wavesplatform/lang/Global.scala b/lang/jvm/src/main/scala/com/wavesplatform/lang/Global.scala
index a56e00fe523..f33e0528ef5 100644
--- a/lang/jvm/src/main/scala/com/wavesplatform/lang/Global.scala
+++ b/lang/jvm/src/main/scala/com/wavesplatform/lang/Global.scala
@@ -1,22 +1,25 @@
 package com.wavesplatform.lang
 
 import com.wavesplatform.lang.v1.BaseGlobal
-import com.wavesplatform.utils.Base58
+import com.wavesplatform.utils.{Base58, Base64}
 import scorex.crypto.hash.{Blake2b256, Keccak256, Sha256}
 import scorex.crypto.signatures.{Curve25519, PublicKey, Signature}
 
 object Global extends BaseGlobal {
-  val MaxBase58Bytes = 64
-  val MaxBase58Chars = 100
-
   def base58Encode(input: Array[Byte]): Either[String, String] =
     if (input.length > MaxBase58Bytes) Left(s"base58Encode input exceeds $MaxBase58Bytes")
     else Right(Base58.encode(input))
 
-  def base58Decode(input: String): Either[String, Array[Byte]] =
-    if (input.length > MaxBase58Chars) Left(s"base58Decode input exceeds $MaxBase58Chars")
+  def base58Decode(input: String, limit: Int): Either[String, Array[Byte]] =
+    if (input.length > limit) Left(s"base58Decode input exceeds $limit")
     else Base58.decode(input).toEither.left.map(_ => "can't parse Base58 string")
 
+  def base64Encode(input: Array[Byte]): Either[String, String] = Right(Base64.encode(input))
+
+  def base64Decode(input: String, limit: Int): Either[String, Array[Byte]] =
+    if (input.length > limit) Left(s"base58Decode input exceeds $limit")
+    else Base64.decode(input).toEither.left.map(_ => "can't parse Base64 string")
+
   def curve25519verify(message: Array[Byte], sig: Array[Byte], pub: Array[Byte]): Boolean = Curve25519.verify(Signature(sig), message, PublicKey(pub))
 
   def keccak256(message: Array[Byte]): Array[Byte]  = Keccak256.hash(message)
diff --git a/lang/jvm/src/main/scala/com/wavesplatform/utils/Base64.scala b/lang/jvm/src/main/scala/com/wavesplatform/utils/Base64.scala
index 78385a6f96e..aae94c82228 100644
--- a/lang/jvm/src/main/scala/com/wavesplatform/utils/Base64.scala
+++ b/lang/jvm/src/main/scala/com/wavesplatform/utils/Base64.scala
@@ -3,10 +3,10 @@ package com.wavesplatform.utils
 import scala.util.Try
 
 object Base64 {
-  def encode(input: Array[Byte]): String = "base64:" + new String(java.util.Base64.getEncoder.encode(input))
+  def encode(input: Array[Byte]): String = new String(java.util.Base64.getEncoder.encode(input))
 
   def decode(input: String): Try[Array[Byte]] = Try {
-    if (!input.startsWith("base64:")) throw new IllegalArgumentException("String of the form base64:chars expected")
-    else java.util.Base64.getDecoder.decode(input.substring(7))
+    val str = if (input.startsWith("base64:")) input.substring(7) else input
+    java.util.Base64.getDecoder.decode(str)
   }
 }
diff --git a/lang/jvm/src/test/scala/com/wavesplatform/lang/ParserTest.scala b/lang/jvm/src/test/scala/com/wavesplatform/lang/ParserTest.scala
index 78d6130dabc..611b3a86053 100644
--- a/lang/jvm/src/test/scala/com/wavesplatform/lang/ParserTest.scala
+++ b/lang/jvm/src/test/scala/com/wavesplatform/lang/ParserTest.scala
@@ -161,12 +161,26 @@ class ParserTest extends PropSpec with PropertyChecks with Matchers with ScriptG
     parseOne("base58' bQbp'") shouldBe CONST_BYTEVECTOR(0, 13, PART.INVALID(8, 12, "can't parse Base58 string"))
   }
 
-  property("long base58 definition") {
-    import Global.MaxBase58Chars
-    val longBase58 = "A" * (MaxBase58Chars + 1)
-    val to         = 8 + MaxBase58Chars
-    parseOne(s"base58'$longBase58'") shouldBe
-      CONST_BYTEVECTOR(0, to + 1, PART.INVALID(8, to, s"base58Decode input exceeds $MaxBase58Chars"))
+  property("valid non-empty base64 definition") {
+    parseOne("base64'TElLRQ=='") shouldBe CONST_BYTEVECTOR(0, 16, PART.VALID(8, 15, ByteVector("LIKE".getBytes)))
+  }
+
+  property("valid empty base64 definition") {
+    parseOne("base64''") shouldBe CONST_BYTEVECTOR(0, 8, PART.VALID(8, 7, ByteVector.empty))
+  }
+
+  property("invalid base64 definition") {
+    parseOne("base64'mid-size'") shouldBe CONST_BYTEVECTOR(0, 16, PART.INVALID(8, 15, "can't parse Base64 string"))
+  }
+
+  property("literal too long") {
+    import Global.MaxLiteralLength
+    val longLiteral = "A" * (MaxLiteralLength + 1)
+    val to          = 8 + MaxLiteralLength
+    parseOne(s"base58'$longLiteral'") shouldBe
+      CONST_BYTEVECTOR(0, to + 1, PART.INVALID(8, to, s"base58Decode input exceeds $MaxLiteralLength"))
+    parseOne(s"base64'base64:$longLiteral'") shouldBe
+      CONST_BYTEVECTOR(0, to + 8, PART.INVALID(8, to + 7, s"base58Decode input exceeds $MaxLiteralLength"))
   }
 
   property("string is consumed fully") {
diff --git a/lang/jvm/src/test/scala/com/wavesplatform/utils/Base64Test.scala b/lang/jvm/src/test/scala/com/wavesplatform/utils/Base64Test.scala
index 5a5d43c76dc..d5282787d30 100644
--- a/lang/jvm/src/test/scala/com/wavesplatform/utils/Base64Test.scala
+++ b/lang/jvm/src/test/scala/com/wavesplatform/utils/Base64Test.scala
@@ -18,10 +18,9 @@ class Base64Test extends PropSpec with PropertyChecks with Matchers {
     } yield chars.mkString
 
   property("handles empty sequences") {
-    Base64.encode(Array.emptyByteArray) shouldBe "base64:"
-    val d = Base64.decode("base64:")
-    d.isSuccess shouldBe true
-    d.get.length shouldBe 0
+    Base64.encode(Array.emptyByteArray) shouldBe ""
+    Base64.decode("").get.length shouldBe 0
+    Base64.decode("base64:").get.length shouldBe 0
   }
 
   property("decoding fails on illegal characters") {
diff --git a/lang/shared/src/main/scala/com/wavesplatform/lang/v1/BaseGlobal.scala b/lang/shared/src/main/scala/com/wavesplatform/lang/v1/BaseGlobal.scala
index 2a1f6e02f5e..4cf97eb4e78 100644
--- a/lang/shared/src/main/scala/com/wavesplatform/lang/v1/BaseGlobal.scala
+++ b/lang/shared/src/main/scala/com/wavesplatform/lang/v1/BaseGlobal.scala
@@ -5,8 +5,15 @@ package com.wavesplatform.lang.v1
   * And IDEA can't find the Global class in the "shared" module, but it must!
   */
 trait BaseGlobal {
+  val MaxBase58Bytes = 64
+  val MaxLiteralLength = 12 * 1024
+  val MaxAddressLength = 36
+
   def base58Encode(input: Array[Byte]): Either[String, String]
-  def base58Decode(input: String): Either[String, Array[Byte]]
+  def base58Decode(input: String, limit: Int = MaxLiteralLength): Either[String, Array[Byte]]
+
+  def base64Encode(input: Array[Byte]): Either[String, String]
+  def base64Decode(input: String, limit: Int = MaxLiteralLength): Either[String, Array[Byte]]
 
   def curve25519verify(message: Array[Byte], sig: Array[Byte], pub: Array[Byte]): Boolean
 
diff --git a/lang/shared/src/main/scala/com/wavesplatform/lang/v1/evaluator/ctx/impl/CryptoContext.scala b/lang/shared/src/main/scala/com/wavesplatform/lang/v1/evaluator/ctx/impl/CryptoContext.scala
index 15242c96067..12d1e8157c6 100644
--- a/lang/shared/src/main/scala/com/wavesplatform/lang/v1/evaluator/ctx/impl/CryptoContext.scala
+++ b/lang/shared/src/main/scala/com/wavesplatform/lang/v1/evaluator/ctx/impl/CryptoContext.scala
@@ -29,6 +29,11 @@ object CryptoContext {
       case (bytes: ByteVector) :: Nil => global.base58Encode(bytes.toArray)
       case _ => ???
     }
-    EvaluationContext.build(Map.empty, Seq(keccak256F, blake2b256F, sha256F, sigVerifyF, toBase58StringF))
+
+    def toBase64StringF: PredefFunction = PredefFunction("toBase64String", 10, STRING, List(("bytes", BYTEVECTOR)), "toBase64String") {
+      case (bytes: ByteVector) :: Nil => global.base64Encode(bytes.toArray)
+      case _ => ???
+    }
+    EvaluationContext.build(Map.empty, Seq(keccak256F, blake2b256F, sha256F, sigVerifyF, toBase58StringF, toBase64StringF))
   }
 }
diff --git a/lang/shared/src/main/scala/com/wavesplatform/lang/v1/evaluator/ctx/impl/EnvironmentFunctions.scala b/lang/shared/src/main/scala/com/wavesplatform/lang/v1/evaluator/ctx/impl/EnvironmentFunctions.scala
index 87025e20875..894eaf989c3 100644
--- a/lang/shared/src/main/scala/com/wavesplatform/lang/v1/evaluator/ctx/impl/EnvironmentFunctions.scala
+++ b/lang/shared/src/main/scala/com/wavesplatform/lang/v1/evaluator/ctx/impl/EnvironmentFunctions.scala
@@ -20,7 +20,7 @@ class EnvironmentFunctions(environment: Environment) {
 
   def addressFromString(str: String): Either[String, Option[ByteVector]] = {
     val base58String = if (str.startsWith(Prefix)) str.drop(Prefix.length) else str
-    Global.base58Decode(base58String) match {
+    Global.base58Decode(base58String, Global.MaxAddressLength) match {
       case Left(e) => Left(e)
       case Right(addressBytes) =>
         val version = addressBytes.head
diff --git a/lang/shared/src/main/scala/com/wavesplatform/lang/v1/parser/Parser.scala b/lang/shared/src/main/scala/com/wavesplatform/lang/v1/parser/Parser.scala
index 2be84d87ecb..a851b77eba9 100644
--- a/lang/shared/src/main/scala/com/wavesplatform/lang/v1/parser/Parser.scala
+++ b/lang/shared/src/main/scala/com/wavesplatform/lang/v1/parser/Parser.scala
@@ -19,7 +19,7 @@ object Parser {
   import White._
   import fastparse.noApi._
 
-  val keywords               = Set("let", "base58", "true", "false", "if", "then", "else", "match", "case")
+  val keywords               = Set("let", "base58", "base64", "true", "false", "if", "then", "else", "match", "case")
   private val lowerChar      = CharIn('a' to 'z')
   private val upperChar      = CharIn('A' to 'Z')
   private val char           = lowerChar | upperChar
@@ -191,12 +191,15 @@ object Parser {
       }
 
   private val byteVectorP: P[EXPR] =
-    P(Index ~~ "base58'" ~/ Pass ~~ CharPred(_ != '\'').repX.! ~~ "'" ~~ Index)
+    P(Index ~~ "base" ~~ ("58" | "64").! ~~ "'" ~/ Pass ~~ CharPred(_ != '\'').repX.! ~~ "'" ~~ Index)
       .map {
-        case (start, xs, end) =>
-          val decoded    = if (xs.isEmpty) Right(Array.emptyByteArray) else Global.base58Decode(xs)
+        case (start, base, xs, end) =>
           val innerStart = start + 8
           val innerEnd   = end - 1
+          val decoded = base match {
+            case "58" => Global.base58Decode(xs)
+            case "64" => Global.base64Decode(xs)
+          }
           decoded match {
             case Left(err) => CONST_BYTEVECTOR(start, end, PART.INVALID(innerStart, innerEnd, err))
             case Right(r)  => CONST_BYTEVECTOR(start, end, PART.VALID(innerStart, innerEnd, ByteVector(r)))
diff --git a/src/main/scala/com/wavesplatform/state/ByteStr.scala b/src/main/scala/com/wavesplatform/state/ByteStr.scala
index 5c58828a668..5865590608a 100644
--- a/src/main/scala/com/wavesplatform/state/ByteStr.scala
+++ b/src/main/scala/com/wavesplatform/state/ByteStr.scala
@@ -15,7 +15,7 @@ case class ByteStr(arr: Array[Byte]) {
 
   lazy val base58: String = Base58.encode(arr)
 
-  lazy val base64: String = Base64.encode(arr)
+  lazy val base64: String = "base64:" + Base64.encode(arr)
 
   lazy val trim: String = base58.toString.take(7) + "..."
 
@@ -24,6 +24,7 @@ case class ByteStr(arr: Array[Byte]) {
 
 object ByteStr {
   def decodeBase58(s: String): Try[ByteStr] = Base58.decode(s).map(ByteStr(_))
+  def decodeBase64(s: String): Try[ByteStr] = Base64.decode(s).map(ByteStr(_))
   val empty: ByteStr                        = ByteStr(Array.emptyByteArray)
 
   implicit val byteStrWrites: Format[ByteStr] = new Format[ByteStr] {
diff --git a/src/main/scala/com/wavesplatform/state/DataEntry.scala b/src/main/scala/com/wavesplatform/state/DataEntry.scala
index b66ee4a77cd..3d689dbb158 100644
--- a/src/main/scala/com/wavesplatform/state/DataEntry.scala
+++ b/src/main/scala/com/wavesplatform/state/DataEntry.scala
@@ -4,7 +4,6 @@ import java.nio.charset.StandardCharsets.UTF_8
 
 import com.google.common.primitives.{Longs, Shorts}
 import com.wavesplatform.state.DataEntry._
-import com.wavesplatform.utils.Base64
 import play.api.libs.json._
 import scorex.serialization.Deser
 
@@ -70,7 +69,7 @@ object DataEntry {
             case JsDefined(JsString("binary")) =>
               jsv \ "value" match {
                 case JsDefined(JsString(enc)) =>
-                  Base64.decode(enc).fold(ex => JsError(ex.getMessage), arr => JsSuccess(BinaryDataEntry(key, ByteStr(arr))))
+                  ByteStr.decodeBase64(enc).fold(ex => JsError(ex.getMessage), bstr => JsSuccess(BinaryDataEntry(key, bstr)))
                 case _ => JsError("value is missing or not a string")
               }
             case JsDefined(JsString("string")) =>
diff --git a/src/test/scala/com/wavesplatform/state/diffs/smart/scenarios/NotaryControlledTransferScenartioTest.scala b/src/test/scala/com/wavesplatform/state/diffs/smart/scenarios/NotaryControlledTransferScenartioTest.scala
index 789c185f249..11553e73179 100644
--- a/src/test/scala/com/wavesplatform/state/diffs/smart/scenarios/NotaryControlledTransferScenartioTest.scala
+++ b/src/test/scala/com/wavesplatform/state/diffs/smart/scenarios/NotaryControlledTransferScenartioTest.scala
@@ -118,15 +118,21 @@ class NotaryControlledTransferScenartioTest extends PropSpec with PropertyChecks
   }
 
   property("Script toBase58String") {
-    eval[Boolean]("toBase58String(base58'AXiXp5CmwVaq4Tp6h6') == \"AXiXp5CmwVaq4Tp6h6\"").explicitGet() shouldBe true
+    val s = "AXiXp5CmwVaq4Tp6h6"
+    eval[Boolean](s"""toBase58String(base58'$s') == \"$s\"""").explicitGet() shouldBe true
+  }
+
+  property("Script toBase64String") {
+    val s = "Kl0pIkOM3tRikA=="
+    eval[Boolean](s"""toBase64String(base64'$s') == \"$s\"""").explicitGet() shouldBe true
   }
 
   property("addressFromString() fails when address is too long") {
-    import Global.MaxBase58Chars
-    val longAddress = "A" * (MaxBase58Chars + 1)
+    import Global.MaxAddressLength
+    val longAddress = "A" * (MaxAddressLength + 1)
     val r           = eval[ByteVector](s"""addressFromString("$longAddress")""")
     r.isLeft shouldBe true
-    r.left.get.toString.contains(s"base58Decode input exceeds $MaxBase58Chars") shouldBe true
+    r.left.get shouldBe s"base58Decode input exceeds $MaxAddressLength"
   }
 
   property("Scenario") {