diff --git a/keypairs.js b/keypairs.js
index 1bbebb4..2ec87ba 100644
--- a/keypairs.js
+++ b/keypairs.js
@@ -240,7 +240,7 @@ Keypairs.signJws = function (opts) {
       if ('EC' === opts.jwk.kty) {
         // ECDSA JWT signatures differ from "normal" ECDSA signatures
         // https://tools.ietf.org/html/rfc7518#section-3.4
-        binsig = convertIfEcdsa(binsig);
+        binsig = ecdsaAsn1SigToJoseSig(binsig);
       }
 
       var sig = binsig.toString('base64')
@@ -257,7 +257,7 @@ Keypairs.signJws = function (opts) {
       };
     }
 
-    function convertIfEcdsa(binsig) {
+    function ecdsaAsn1SigToJoseSig(binsig) {
       // should have asn1 sequence header of 0x30
       if (0x30 !== binsig[0]) { throw new Error("Impossible EC SHA head marker"); }
       var index = 2; // first ecdsa "R" header byte