diff --git a/src/core/operations/ECDSASign.mjs b/src/core/operations/ECDSASign.mjs
index d7bd32e0..5cce8cc2 100644
--- a/src/core/operations/ECDSASign.mjs
+++ b/src/core/operations/ECDSASign.mjs
@@ -47,7 +47,7 @@ class ECDSASign extends Operation {
                 type: "option",
                 value: [
                     "ASN.1 HEX",
-                    "Concat HEX",
+                    "P1363 HEX",
                     "JSON"
                 ]
             }
@@ -83,7 +83,7 @@ class ECDSASign extends Operation {
             case "ASN.1 HEX":
                 result = signatureASN1Hex;
                 break;
-            case "Concat HEX":
+            case "P1363 HEX":
                 result = r.KJUR.crypto.ECDSA.asn1SigToConcatSig(signatureASN1Hex);
                 break;
             case "JSON": {
diff --git a/src/core/operations/ECDSASignatureConversion.mjs b/src/core/operations/ECDSASignatureConversion.mjs
index fe5dc3c2..1dfcb4d1 100644
--- a/src/core/operations/ECDSASignatureConversion.mjs
+++ b/src/core/operations/ECDSASignatureConversion.mjs
@@ -31,7 +31,7 @@ class ECDSASignatureConversion extends Operation {
                 value: [
                     "Auto",
                     "ASN.1 HEX",
-                    "Concat HEX",
+                    "P1363 HEX",
                     "JSON"
                 ]
             },
@@ -40,7 +40,7 @@ class ECDSASignatureConversion extends Operation {
                 type: "option",
                 value: [
                     "ASN.1 HEX",
-                    "Concat HEX",
+                    "P1363 HEX",
                     "JSON"
                 ]
             }
@@ -63,7 +63,7 @@ class ECDSASignatureConversion extends Operation {
             } else if (input.indexOf("{") !== -1) {
                 inputFormat = "JSON";
             } else {
-                inputFormat = "Concat HEX";
+                inputFormat = "P1363 HEX";
             }
         }
 
@@ -73,7 +73,7 @@ class ECDSASignatureConversion extends Operation {
             case "ASN.1 HEX":
                 signatureASN1Hex = input;
                 break;
-            case "Concat HEX":
+            case "P1363 HEX":
                 signatureASN1Hex = r.KJUR.crypto.ECDSA.concatSigToASN1Sig(input);
                 break;
             case "JSON": {
@@ -89,7 +89,7 @@ class ECDSASignatureConversion extends Operation {
             case "ASN.1 HEX":
                 result = signatureASN1Hex;
                 break;
-            case "Concat HEX":
+            case "P1363 HEX":
                 result = r.KJUR.crypto.ECDSA.asn1SigToConcatSig(signatureASN1Hex);
                 break;
             case "JSON": {
diff --git a/src/core/operations/ECDSAVerify.mjs b/src/core/operations/ECDSAVerify.mjs
index 68e3a1aa..8f3174a2 100644
--- a/src/core/operations/ECDSAVerify.mjs
+++ b/src/core/operations/ECDSAVerify.mjs
@@ -32,7 +32,7 @@ class ECDSAVerify extends Operation {
                 value: [
                     "Auto",
                     "ASN.1 HEX",
-                    "Concat HEX",
+                    "P1363 HEX",
                     "JSON"
                 ]
             },
@@ -80,7 +80,7 @@ class ECDSAVerify extends Operation {
             } else if (input.indexOf("{") !== -1) {
                 inputFormat = "JSON";
             } else {
-                inputFormat = "Concat HEX";
+                inputFormat = "P1363 HEX";
             }
         }
 
@@ -90,7 +90,7 @@ class ECDSAVerify extends Operation {
             case "ASN.1 HEX":
                 signatureASN1Hex = input;
                 break;
-            case "Concat HEX":
+            case "P1363 HEX":
                 signatureASN1Hex = r.KJUR.crypto.ECDSA.concatSigToASN1Sig(input);
                 break;
             case "JSON": {
diff --git a/tests/operations/tests/ECDSA.mjs b/tests/operations/tests/ECDSA.mjs
index dd3013d3..8fe93ef3 100644
--- a/tests/operations/tests/ECDSA.mjs
+++ b/tests/operations/tests/ECDSA.mjs
@@ -30,7 +30,7 @@ gusgcAE8H6810fkJ8ZmTNiCCa6sLgR2vD1VNh2diirWgKPH4PVMKav5e6Q==
     signature: {
         sha256: {
             asn1: "3046022100e06905608a2fa7dbda9e284c2a7959dfb68fb527a5f003b2d7975ff135145127022100b6baa253793334f8b93ea1dd622bc600124d8090babd807efe3f77b8b324388d",
-            concat: "e06905608a2fa7dbda9e284c2a7959dfb68fb527a5f003b2d7975ff135145127b6baa253793334f8b93ea1dd622bc600124d8090babd807efe3f77b8b324388d",
+            p1363: "e06905608a2fa7dbda9e284c2a7959dfb68fb527a5f003b2d7975ff135145127b6baa253793334f8b93ea1dd622bc600124d8090babd807efe3f77b8b324388d",
             json: `{"r":"00e06905608a2fa7dbda9e284c2a7959dfb68fb527a5f003b2d7975ff135145127","s":"00b6baa253793334f8b93ea1dd622bc600124d8090babd807efe3f77b8b324388d"}`
         }
     }
@@ -250,8 +250,8 @@ TestRegister.addTests([
         ]
     },
     {
-        name: "ECDSA Verify: P-256 with SHA256 (Concat signature)",
-        input: P256.signature.sha256.concat,
+        name: "ECDSA Verify: P-256 with SHA256 (P1363 signature)",
+        input: P256.signature.sha256.p1363,
         expectedOutput: "Verified OK",
         recipeConfig: [
             {
@@ -307,13 +307,13 @@ TestRegister.addTests([
         ]
     },
     {
-        name: "ECDSA Signature Conversion: ASN.1 To Concat",
+        name: "ECDSA Signature Conversion: ASN.1 To P1363",
         input: P256.signature.sha256.asn1,
-        expectedOutput: P256.signature.sha256.concat,
+        expectedOutput: P256.signature.sha256.p1363,
         recipeConfig: [
             {
                 "op": "ECDSA Signature Conversion",
-                "args": ["Auto", "Concat HEX"]
+                "args": ["Auto", "P1363 HEX"]
             }
         ]
     },
@@ -329,8 +329,8 @@ TestRegister.addTests([
         ]
     },
     {
-        name: "ECDSA Signature Conversion: Concat To ASN.1",
-        input: P256.signature.sha256.concat,
+        name: "ECDSA Signature Conversion: P1363 To ASN.1",
+        input: P256.signature.sha256.p1363,
         expectedOutput: P256.signature.sha256.asn1,
         recipeConfig: [
             {
@@ -340,19 +340,19 @@ TestRegister.addTests([
         ]
     },
     {
-        name: "ECDSA Signature Conversion: Concat To Concat",
-        input: P256.signature.sha256.concat,
-        expectedOutput: P256.signature.sha256.concat,
+        name: "ECDSA Signature Conversion: P1363 To P1363",
+        input: P256.signature.sha256.p1363,
+        expectedOutput: P256.signature.sha256.p1363,
         recipeConfig: [
             {
                 "op": "ECDSA Signature Conversion",
-                "args": ["Auto", "Concat HEX"]
+                "args": ["Auto", "P1363 HEX"]
             }
         ]
     },
     {
-        name: "ECDSA Signature Conversion: Concat To JSON",
-        input: P256.signature.sha256.concat,
+        name: "ECDSA Signature Conversion: P1363 To JSON",
+        input: P256.signature.sha256.p1363,
         expectedOutput: P256.signature.sha256.json,
         recipeConfig: [
             {
@@ -373,13 +373,13 @@ TestRegister.addTests([
         ]
     },
     {
-        name: "ECDSA Signature Conversion: JSON To Concat",
+        name: "ECDSA Signature Conversion: JSON To P1363",
         input: P256.signature.sha256.json,
-        expectedOutput: P256.signature.sha256.concat,
+        expectedOutput: P256.signature.sha256.p1363,
         recipeConfig: [
             {
                 "op": "ECDSA Signature Conversion",
-                "args": ["Auto", "Concat HEX"]
+                "args": ["Auto", "P1363 HEX"]
             }
         ]
     },