diff --git a/cache.go b/cache.go
index d4ad4f7..8ca9aca 100644
--- a/cache.go
+++ b/cache.go
@@ -35,7 +35,7 @@ func (c *Cache) Get(key string) (string, bool) {
 // Put stores a result, evicting the least recently used entry if full.
 func (c *Cache) Put(key, val string) {
 	key = NormalizeKey(key)
-	if _, exists := c.data[key]; !exists && len(c.data) >= c.cap {
+	if _, exists := c.data[key]; !exists && len(c.data) > c.cap {
 		c.evict()
 	}
 	c.data[key] = val