diff --git a/README.md b/README.md
index 3f0aba8..705465b 100644
--- a/README.md
+++ b/README.md
@@ -1,5 +1,5 @@
 # headlong-cli
-Command line interface for https://github.com/esaulpaugh/headlong ABI and RLP codecs. Depends on headlong v12.2.0 and gson v2.10.1. Licensed under Apache 2.0 terms.
+Command line interface for https://github.com/esaulpaugh/headlong ABI and RLP codecs. Depends on headlong v12.3.0 and gson v2.10.1. Licensed under Apache 2.0 terms.
 
 ## Build
 
diff --git a/build.gradle b/build.gradle
index 6c05d2e..f714e24 100644
--- a/build.gradle
+++ b/build.gradle
@@ -25,7 +25,7 @@ repositories {
 //    mavenLocal()
 }
 
-final String headlongVersion = '12.1.0'
+final String headlongVersion = '12.3.0'
 final String junitVersion = '5.10.3'
 final DateTimeFormatter dateFormatter = DateTimeFormatter.ofPattern("MMMM d yyyy", Locale.ENGLISH).withZone(ZoneId.of("UTC"))
 
diff --git a/gradle/verification-metadata.xml b/gradle/verification-metadata.xml
index 33b3aba..a6b3c17 100644
--- a/gradle/verification-metadata.xml
+++ b/gradle/verification-metadata.xml
@@ -6,7 +6,7 @@
       <key-servers enabled="true"/>
       <trusted-keys>
          <trusted-key id="c7be5bcc9fec15518cfda882b0f3710fa64900e7" group="com.google.code.gson"/>
-         <trusted-key id="d2ea6bcd43b3663cdf6222c135ae09fd38f0cfae" group="com.esaulpaugh" name="headlong" version="12.1.0"/><!-- *** REMEMBER TO UPDATE VERSION ** -->
+         <trusted-key id="d2ea6bcd43b3663cdf6222c135ae09fd38f0cfae" group="com.esaulpaugh" name="headlong" version="12.3.0"/><!-- *** REMEMBER TO UPDATE VERSION ** -->
          <trusted-key id="ff6e2c001948c5f2f38b0cc385911f425ec61b51">
             <trusting group="^org[.]junit($|([.].*))" regex="true"/>
             <trusting group="org.opentest4j"/>
diff --git a/pom.xml b/pom.xml
index fc5be9a..49eed70 100644
--- a/pom.xml
+++ b/pom.xml
@@ -20,7 +20,7 @@
         <argLine>-Dfile.encoding=UTF-8</argLine>
         <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
         <maven.build.timestamp.format>MMMMM d yyyy</maven.build.timestamp.format>
-        <headlong.version>12.2.0</headlong.version>
+        <headlong.version>12.3.0</headlong.version>
         <junit.version>5.10.3</junit.version>
     </properties>