diff --git a/cmdgen.c b/cmdgen.c
index 5c17ce2b..7ec6dbae 100644
--- a/cmdgen.c
+++ b/cmdgen.c
@@ -486,7 +486,7 @@ int main(int argc, char **argv)
             bits = 384;
             break;
           case ED25519:
-            bits = 256;
+            bits = 255;
             break;
           default:
             bits = DEFAULT_RSADSA_BITS;
@@ -499,8 +499,8 @@ int main(int argc, char **argv)
         errs = true;
     }
 
-    if (keytype == ED25519 && (bits != 256)) {
-        fprintf(stderr, "puttygen: invalid bits for ED25519, choose 256\n");
+    if (keytype == ED25519 && (bits != 255) && (bits != 256)) {
+        fprintf(stderr, "puttygen: invalid bits for ED25519, choose 255\n");
         errs = true;
     }
 
diff --git a/sshecc.c b/sshecc.c
index dd9a7e3e..3005e288 100644
--- a/sshecc.c
+++ b/sshecc.c
@@ -1549,7 +1549,7 @@ bool ec_ed_alg_and_curve_by_bits(
     int bits, const struct ec_curve **curve, const ssh_keyalg **alg)
 {
     switch (bits) {
-      case 256: *alg = &ssh_ecdsa_ed25519; break;
+      case 255: case 256: *alg = &ssh_ecdsa_ed25519; break;
       default: return false;
     }
     *curve = ((struct ecsign_extra *)(*alg)->extra)->curve();
diff --git a/windows/winpgen.c b/windows/winpgen.c
index 353caa02..efb9a392 100644
--- a/windows/winpgen.c
+++ b/windows/winpgen.c
@@ -365,7 +365,7 @@ static DWORD WINAPI generate_key_thread(void *param)
         ecdsa_generate(params->eckey, params->curve_bits,
                        progress_update, &prog);
     else if (params->keytype == ED25519)
-        eddsa_generate(params->edkey, 256, progress_update, &prog);
+        eddsa_generate(params->edkey, 255, progress_update, &prog);
     else
         rsa_generate(params->key, params->key_bits, progress_update, &prog);