diff --git a/src/mcts.c b/src/mcts.c
index cb241fb..414219c 100644
--- a/src/mcts.c
+++ b/src/mcts.c
@@ -50,38 +50,72 @@ static fixed_point_t fixed_sqrt(fixed_point_t x)
     return s;
 }
 
-static fixed_point_t fixed_log(fixed_point_t v)
+#define LOG2_TABLE_SIZE 10
+static unsigned log2_table[1U << LOG2_TABLE_SIZE];
+static void log2_table_init(void)
+{
+    /*
+     * Q0.32 fixed-point representation of
+     * 2^{1/2}-1, 2^{1/4}-1, ..., 2^{2^{-32}}-1
+     */
+    const unsigned jump[32] = {
+        1779033704, 812638371, 388727752, 190154448, 94047537, 46769127,
+        23321248,   11644838,  5818478,   2908254,   1453881,  726879,
+        363424,     181708,    90853,     45426,     22713,    11357,
+        5678,       2839,      1420,      710,       355,      177,
+        89,         44,        22,        11,        6,        3,
+        1,          1};
+
+    for (unsigned i = 0; i < (1U << LOG2_TABLE_SIZE); ++i) {
+        /*
+         * Use binary search to find the largest log2(1+x) <= log2(1+i/1024)
+         */
+        u64 target = (u64) i << (64 - LOG2_TABLE_SIZE), now = 0;
+        unsigned log = 0;
+        for (unsigned j = 0; j < 32; ++j) {
+            /* (1+now) * (1+jump) = 1 + now + jump + now*jump */
+            u64 t = ((now + (1U << 31)) >> 32) * jump[j];
+            if (now + ((u64) jump[j] << 32) + t <= target) {
+                now += ((u64) jump[j] << 32) + t;
+                log |= 1U << (31 - j);
+            }
+        }
+        log2_table[i] = log;
+    }
+}
+
+static fixed_point_t fixed_log2(fixed_point_t v)
 {
     if (!v || v == (1U << FIXED_SCALE_BITS))
         return 0;
 
-    fixed_point_t numerator = (v - (1U << FIXED_SCALE_BITS));
-    int neg = 0;
-    if (GET_SIGN(numerator)) {
-        neg = 1;
-        numerator = CLR_SIGN(numerator);
-        numerator = (1U << 31) - numerator;
-    }
+    int log2_v = 15 - __builtin_clz(v);
+    v <<= (15 - log2_v);
+    fixed_point_t int_part = (unsigned) log2_v << FIXED_SCALE_BITS;
 
-    fixed_point_t y = ((u64) numerator << FIXED_SCALE_BITS) /
-                      ((u64) v + (1U << FIXED_SCALE_BITS));
+    unsigned index = (v ^ (1U << 31)) >> (31 - LOG2_TABLE_SIZE);
+    unsigned lower = log2_table[index];
+    unsigned upper =
+        index == (1 << LOG2_TABLE_SIZE) - 1 ? 0 : log2_table[index + 1];
 
-    fixed_point_t ans = 0U;
-    for (unsigned i = 1; i < 20; i += 2) {
-        fixed_point_t z = (1U << FIXED_SCALE_BITS);
-        for (int j = 0; j < i; j++) {
-            z = ((u64) z * y) >> FIXED_SCALE_BITS;
-        }
-        z = ((u64) z << FIXED_SCALE_BITS) / (i << FIXED_SCALE_BITS);
+    unsigned offset = v & ((1U << (31 - LOG2_TABLE_SIZE)) - 1);
+    u64 frac_part =
+        lower +
+        (((u64) (upper - lower) * offset + (1U << (30 - LOG2_TABLE_SIZE))) >>
+         (31 - LOG2_TABLE_SIZE));
 
-        ans += z;
-    }
-    ans <<= 1;
-    ans = neg ? SET_SIGN(ans) : ans;
-    return ans;
+    unsigned result = int_part + ((frac_part + (1U << 15)) >> 16);
+
+    /* Convert from 2's complement to signed representation */
+    if (GET_SIGN(result))
+        result = SET_SIGN(-result);
+
+    return result;
 }
 
-#define EXPLORATION_FACTOR fixed_sqrt(1U << (FIXED_SCALE_BITS + 1))
+#define SQRT_LOG_2 54562
+#define EXPLORATION_FACTOR \
+    (fixed_sqrt(1U << (FIXED_SCALE_BITS + 1)) * SQRT_LOG_2 >> FIXED_SCALE_BITS)
 
 static inline fixed_point_t uct_score(int n_total, int n_visits, u64 score)
 {
@@ -89,7 +123,7 @@ static inline fixed_point_t uct_score(int n_total, int n_visits, u64 score)
         return FIXED_MAX;
 
     fixed_point_t result = (fixed_point_t) (score / n_visits);
-    fixed_point_t log_val = fixed_log(
+    fixed_point_t log_val = fixed_log2(
         (n_total < 65536) ? (n_total << FIXED_SCALE_BITS) : FIXED_MAX);
     fixed_point_t tmp =
         ((u64) EXPLORATION_FACTOR * fixed_sqrt(log_val / n_visits)) >>
@@ -219,5 +253,6 @@ int mcts(uint32_t table, char player)
 void mcts_init(void)
 {
     xoro_init(&(mcts_obj.xoro_obj));
+    log2_table_init();
     mcts_obj.nr_active_nodes = 0;
 }