diff --git a/Makefile b/Makefile
index 84577c7..1de773f 100644
--- a/Makefile
+++ b/Makefile
@@ -11,7 +11,7 @@ ldflags= \
 -X "github.com/mike76-dev/hostscore/internal/build.NodeBinaryName=hsd" \
 -X "github.com/mike76-dev/hostscore/internal/build.NodeVersion=1.1.2" \
 -X "github.com/mike76-dev/hostscore/internal/build.ClientBinaryName=hsc" \
--X "github.com/mike76-dev/hostscore/internal/build.ClientVersion=1.4.0" \
+-X "github.com/mike76-dev/hostscore/internal/build.ClientVersion=1.4.1" \
 -X "github.com/mike76-dev/hostscore/internal/build.GitRevision=${GIT_DIRTY}${GIT_REVISION}" \
 -X "github.com/mike76-dev/hostscore/internal/build.BuildTime=${BUILD_TIME}"
 
diff --git a/cmd/hsc/api.go b/cmd/hsc/api.go
index 18f51b2..2ff5ded 100644
--- a/cmd/hsc/api.go
+++ b/cmd/hsc/api.go
@@ -191,6 +191,7 @@ type portalAPI struct {
 	stopChan chan struct{}
 	averages map[string]map[string]networkAverages
 	nodes    map[string]nodeStatus
+	rl       *ratelimiter
 }
 
 func newAPI(s *jsonStore, db *sql.DB, token string, logger *zap.Logger, cache *responseCache) (*portalAPI, error) {
@@ -210,6 +211,8 @@ func newAPI(s *jsonStore, db *sql.DB, token string, logger *zap.Logger, cache *r
 	api.hosts["mainnet"] = make(map[types.PublicKey]*portalHost)
 	api.hosts["zen"] = make(map[types.PublicKey]*portalHost)
 
+	api.rl = newRatelimiter(api.stopChan)
+
 	err := api.load()
 	if err != nil {
 		return nil, err
@@ -370,6 +373,10 @@ func (api *portalAPI) buildHTTPRoutes() {
 }
 
 func (api *portalAPI) hostsHostHandler(w http.ResponseWriter, req *http.Request, _ httprouter.Params) {
+	if api.rl.limitExceeded(getRemoteHost(req)) {
+		writeError(w, "too many requests", http.StatusTooManyRequests)
+		return
+	}
 	network := strings.ToLower(req.FormValue("network"))
 	if network == "" {
 		network = "mainnet"
@@ -406,6 +413,10 @@ func (api *portalAPI) hostsHostHandler(w http.ResponseWriter, req *http.Request,
 }
 
 func (api *portalAPI) hostsHandler(w http.ResponseWriter, req *http.Request, _ httprouter.Params) {
+	if api.rl.limitExceeded(getRemoteHost(req)) {
+		writeError(w, "too many requests", http.StatusTooManyRequests)
+		return
+	}
 	network := strings.ToLower(req.FormValue("network"))
 	if network == "" {
 		network = "mainnet"
@@ -513,6 +524,10 @@ func (api *portalAPI) hostsHandler(w http.ResponseWriter, req *http.Request, _ h
 }
 
 func (api *portalAPI) hostsKeysHandler(w http.ResponseWriter, req *http.Request, _ httprouter.Params) {
+	if api.rl.limitExceeded(getRemoteHost(req)) {
+		writeError(w, "too many requests", http.StatusTooManyRequests)
+		return
+	}
 	err := req.ParseForm()
 	if err != nil {
 		writeError(w, "unable to parse request", http.StatusBadRequest)
@@ -678,6 +693,10 @@ func (api *portalAPI) hostsKeysHandler(w http.ResponseWriter, req *http.Request,
 }
 
 func (api *portalAPI) hostsScansHandler(w http.ResponseWriter, req *http.Request, _ httprouter.Params) {
+	if api.rl.limitExceeded(getRemoteHost(req)) {
+		writeError(w, "too many requests", http.StatusTooManyRequests)
+		return
+	}
 	network := strings.ToLower(req.FormValue("network"))
 	if network == "" {
 		network = "mainnet"
@@ -752,6 +771,10 @@ func (api *portalAPI) hostsScansHandler(w http.ResponseWriter, req *http.Request
 }
 
 func (api *portalAPI) hostsBenchmarksHandler(w http.ResponseWriter, req *http.Request, _ httprouter.Params) {
+	if api.rl.limitExceeded(getRemoteHost(req)) {
+		writeError(w, "too many requests", http.StatusTooManyRequests)
+		return
+	}
 	network := strings.ToLower(req.FormValue("network"))
 	if network == "" {
 		network = "mainnet"
@@ -835,7 +858,11 @@ func balanceStatus(balance types.Currency) string {
 	return "ok"
 }
 
-func (api *portalAPI) serviceStatusHandler(w http.ResponseWriter, _ *http.Request, _ httprouter.Params) {
+func (api *portalAPI) serviceStatusHandler(w http.ResponseWriter, req *http.Request, _ httprouter.Params) {
+	if api.rl.limitExceeded(getRemoteHost(req)) {
+		writeError(w, "too many requests", http.StatusTooManyRequests)
+		return
+	}
 	writeJSON(w, statusResponse{
 		Version: build.ClientVersion,
 		Nodes:   api.nodes,
@@ -843,6 +870,10 @@ func (api *portalAPI) serviceStatusHandler(w http.ResponseWriter, _ *http.Reques
 }
 
 func (api *portalAPI) networkHostsHandler(w http.ResponseWriter, req *http.Request, _ httprouter.Params) {
+	if api.rl.limitExceeded(getRemoteHost(req)) {
+		writeError(w, "too many requests", http.StatusTooManyRequests)
+		return
+	}
 	network := strings.ToLower(req.FormValue("network"))
 	if network == "" {
 		network = "mainnet"
@@ -864,6 +895,10 @@ func (api *portalAPI) networkHostsHandler(w http.ResponseWriter, req *http.Reque
 }
 
 func (api *portalAPI) hostsChangesHandler(w http.ResponseWriter, req *http.Request, _ httprouter.Params) {
+	if api.rl.limitExceeded(getRemoteHost(req)) {
+		writeError(w, "too many requests", http.StatusTooManyRequests)
+		return
+	}
 	network := strings.ToLower(req.FormValue("network"))
 	if network == "" {
 		network = "mainnet"
@@ -923,6 +958,10 @@ func (api *portalAPI) hostsChangesHandler(w http.ResponseWriter, req *http.Reque
 }
 
 func (api *portalAPI) networkAveragesHandler(w http.ResponseWriter, req *http.Request, _ httprouter.Params) {
+	if api.rl.limitExceeded(getRemoteHost(req)) {
+		writeError(w, "too many requests", http.StatusTooManyRequests)
+		return
+	}
 	network := strings.ToLower(req.FormValue("network"))
 	if network == "" {
 		network = "mainnet"
@@ -935,6 +974,10 @@ func (api *portalAPI) networkAveragesHandler(w http.ResponseWriter, req *http.Re
 }
 
 func (api *portalAPI) networkCountriesHandler(w http.ResponseWriter, req *http.Request, _ httprouter.Params) {
+	if api.rl.limitExceeded(getRemoteHost(req)) {
+		writeError(w, "too many requests", http.StatusTooManyRequests)
+		return
+	}
 	network := strings.ToLower(req.FormValue("network"))
 	if network == "" {
 		network = "mainnet"
diff --git a/cmd/hsc/ratelimit.go b/cmd/hsc/ratelimit.go
new file mode 100644
index 0000000..67a5486
--- /dev/null
+++ b/cmd/hsc/ratelimit.go
@@ -0,0 +1,60 @@
+package main
+
+import (
+	"net"
+	"net/http"
+	"sync"
+	"time"
+)
+
+const maxRequestsPerSecond = 10
+
+// ratelimiter keeps the API request stats and determines whether
+// to allow the request or not.
+type ratelimiter struct {
+	requests map[string]int
+	mu       sync.Mutex
+}
+
+func newRatelimiter(stopChan chan struct{}) *ratelimiter {
+	rl := &ratelimiter{
+		requests: make(map[string]int),
+	}
+
+	ticker := time.Tick(time.Second)
+	go func() {
+		for range ticker {
+			select {
+			case <-stopChan:
+				return
+			default:
+			}
+			rl.mu.Lock()
+			rl.requests = make(map[string]int)
+			rl.mu.Unlock()
+		}
+	}()
+
+	return rl
+}
+
+// limitExceeded returns true if there are too many requests from the given host.
+func (rl *ratelimiter) limitExceeded(addr string) bool {
+	rl.mu.Lock()
+	defer rl.mu.Unlock()
+
+	rl.requests[addr]++
+	return rl.requests[addr] > maxRequestsPerSecond
+}
+
+// getRemoteHost returns the address of the remote host.
+func getRemoteHost(r *http.Request) (host string) {
+	host, _, _ = net.SplitHostPort(r.RemoteAddr)
+	if host == "127.0.0.1" || host == "localhost" {
+		xff := r.Header.Values("X-Forwarded-For")
+		if len(xff) > 0 {
+			host = xff[0]
+		}
+	}
+	return
+}