diff --git a/Source/Initialization/WarpXInitData.cpp b/Source/Initialization/WarpXInitData.cpp
index e0c095918fa..ff2ca01deec 100644
--- a/Source/Initialization/WarpXInitData.cpp
+++ b/Source/Initialization/WarpXInitData.cpp
@@ -1024,7 +1024,7 @@ WarpX::InitializeExternalFieldsOnGridUsingParser (
                 const amrex::Real x = 0._rt;
                 const amrex::Real y = 0._rt;
                 const amrex::Real fac_z = (1._rt - x_nodal_flag[0]) * dx_lev[0] * 0.5_rt;
-                const amrex::Real z = j*dx_lev[0] + real_box.lo(0) + fac_z;
+                const amrex::Real z = i*dx_lev[0] + real_box.lo(0) + fac_z;
 #elif defined(WARPX_DIM_XZ) || defined(WARPX_DIM_RZ)
                 const amrex::Real fac_x = (1._rt - x_nodal_flag[0]) * dx_lev[0] * 0.5_rt;
                 const amrex::Real x = i*dx_lev[0] + real_box.lo(0) + fac_x;
@@ -1059,7 +1059,7 @@ WarpX::InitializeExternalFieldsOnGridUsingParser (
                 const amrex::Real x = 0._rt;
                 const amrex::Real y = 0._rt;
                 const amrex::Real fac_z = (1._rt - y_nodal_flag[0]) * dx_lev[0] * 0.5_rt;
-                const amrex::Real z = j*dx_lev[0] + real_box.lo(0) + fac_z;
+                const amrex::Real z = i*dx_lev[0] + real_box.lo(0) + fac_z;
 #elif defined(WARPX_DIM_XZ) || defined(WARPX_DIM_RZ)
                 const amrex::Real fac_x = (1._rt - y_nodal_flag[0]) * dx_lev[0] * 0.5_rt;
                 const amrex::Real x = i*dx_lev[0] + real_box.lo(0) + fac_x;
@@ -1090,7 +1090,7 @@ WarpX::InitializeExternalFieldsOnGridUsingParser (
                 const amrex::Real x = 0._rt;
                 const amrex::Real y = 0._rt;
                 const amrex::Real fac_z = (1._rt - z_nodal_flag[0]) * dx_lev[0] * 0.5_rt;
-                const amrex::Real z = j*dx_lev[0] + real_box.lo(0) + fac_z;
+                const amrex::Real z = i*dx_lev[0] + real_box.lo(0) + fac_z;
 #elif defined(WARPX_DIM_XZ) || defined(WARPX_DIM_RZ)
                 const amrex::Real fac_x = (1._rt - z_nodal_flag[0]) * dx_lev[0] * 0.5_rt;
                 const amrex::Real x = i*dx_lev[0] + real_box.lo(0) + fac_x;