diff --git a/copyparty/httpcli.py b/copyparty/httpcli.py
index 36f747f9..8866f817 100644
--- a/copyparty/httpcli.py
+++ b/copyparty/httpcli.py
@@ -638,7 +638,7 @@ class HttpCli(object):
             penalty = 0.7
             t_idle = t0 - idx.p_end
             if idx.p_dur > 0.7 and t_idle < penalty:
-                m = "rate-limit ({:.1f} sec), cost {:.2f}, idle {:.2f}"
+                m = "rate-limit {:.1f} sec, cost {:.2f}, idle {:.2f}"
                 raise Pebkac(429, m.format(penalty, idx.p_dur, t_idle))
 
         if "srch" in body:
diff --git a/copyparty/web/up2k.js b/copyparty/web/up2k.js
index 8cf00487..de37c6d5 100644
--- a/copyparty/web/up2k.js
+++ b/copyparty/web/up2k.js
@@ -740,9 +740,17 @@ function up2k_init(subtle) {
 
     function handshakes_permitted() {
         var lim = multitask ? 1 : 0;
-        return lim >=
+
+        if (lim <
             st.todo.upload.length +
-            st.busy.upload.length;
+            st.busy.upload.length)
+            return false;
+
+        var cd = st.todo.handshake.length ? st.todo.handshake[0].cooldown : 0;
+        if (cd && cd - Date.now() > 0)
+            return false;
+
+        return true;
     }
 
     function hashing_permitted() {
@@ -1155,6 +1163,15 @@ function up2k_init(subtle) {
                 if (rsp.indexOf('<pre>') === 0)
                     rsp = rsp.slice(5);
 
+                if (rsp.indexOf('rate-limit ') !== -1) {
+                    var penalty = rsp.replace(/.*rate-limit /, "").split(' ')[0];
+                    console.log("rate-limit: " + penalty);
+                    t.cooldown = Date.now() + parseFloat(penalty) * 1000;
+                    st.busy.handshake.splice(st.busy.handshake.indexOf(t), 1);
+                    st.todo.handshake.unshift(t);
+                    return;
+                }
+
                 st.bytes.uploaded += t.size;
                 if (rsp.indexOf('partial upload exists') !== -1 ||
                     rsp.indexOf('file already exists') !== -1) {