diff --git a/bet_calc.py b/bet_calc.py
new file mode 100644
index 0000000..616468e
--- /dev/null
+++ b/bet_calc.py
@@ -0,0 +1,22 @@
+
+
+
+
+def american_odds_to_probability(odds: int) -> float:
+    """
+    根据美式赔率计算概率（以小数形式返回）
+    :param odds: 美式赔率（正数或负数）
+    :return: 概率（0~1之间的小数）
+    """
+    if odds > 0:
+        probability = 100 / (odds + 100)
+    else:
+        probability = abs(odds) / (abs(odds) + 100)
+    return probability
+
+# 示例
+if __name__ == "__main__":
+    odds_list = [+150, -200, +300, -120]
+    for odds in odds_list:
+        prob = american_odds_to_probability(odds)
+        print(f"赔率 {odds}: 概率 {prob:.4f}")
\ No newline at end of file