diff --git a/third_party/sqlite-vec/sqlite-vec.c b/third_party/sqlite-vec/sqlite-vec.c
index 6b06f0bf..fe6090c2 100644
--- a/third_party/sqlite-vec/sqlite-vec.c
+++ b/third_party/sqlite-vec/sqlite-vec.c
@@ -280,22 +280,25 @@ static i32 l1_int8_neon(const void *pVect1v, const void *pVect2v,
     int8x16_t v1 = vld1q_s8(pVect1);
     int8x16_t v2 = vld1q_s8(pVect2);
     int8x16_t diff1 = vabdq_s8(v1, v2);
-    acc1 = vaddq_s32(acc1, vpaddlq_u16(vpaddlq_u8(diff1)));
+    // vabdq_s8 returns signed vector bits; reinterpret them as unsigned
+    // before widening so absolute differences in the 128..255 range are
+    // accumulated without sign extension.
+    acc1 = vaddq_s32(acc1, vpaddlq_u16(vpaddlq_u8(vreinterpretq_u8_s8(diff1))));
 
     v1 = vld1q_s8(pVect1 + 16);
     v2 = vld1q_s8(pVect2 + 16);
     int8x16_t diff2 = vabdq_s8(v1, v2);
-    acc2 = vaddq_s32(acc2, vpaddlq_u16(vpaddlq_u8(diff2)));
+    acc2 = vaddq_s32(acc2, vpaddlq_u16(vpaddlq_u8(vreinterpretq_u8_s8(diff2))));
 
     v1 = vld1q_s8(pVect1 + 32);
     v2 = vld1q_s8(pVect2 + 32);
     int8x16_t diff3 = vabdq_s8(v1, v2);
-    acc3 = vaddq_s32(acc3, vpaddlq_u16(vpaddlq_u8(diff3)));
+    acc3 = vaddq_s32(acc3, vpaddlq_u16(vpaddlq_u8(vreinterpretq_u8_s8(diff3))));
 
     v1 = vld1q_s8(pVect1 + 48);
     v2 = vld1q_s8(pVect2 + 48);
     int8x16_t diff4 = vabdq_s8(v1, v2);
-    acc4 = vaddq_s32(acc4, vpaddlq_u16(vpaddlq_u8(diff4)));
+    acc4 = vaddq_s32(acc4, vpaddlq_u16(vpaddlq_u8(vreinterpretq_u8_s8(diff4))));
 
     pVect1 += 64;
     pVect2 += 64;
@@ -305,7 +308,7 @@ static i32 l1_int8_neon(const void *pVect1v, const void *pVect2v,
     int8x16_t v1 = vld1q_s8(pVect1);
     int8x16_t v2 = vld1q_s8(pVect2);
     int8x16_t diff = vabdq_s8(v1, v2);
-    acc1 = vaddq_s32(acc1, vpaddlq_u16(vpaddlq_u8(diff)));
+    acc1 = vaddq_s32(acc1, vpaddlq_u16(vpaddlq_u8(vreinterpretq_u8_s8(diff))));
     pVect1 += 16;
     pVect2 += 16;
   }