diff --git a/examples/selectvpc/main.tf b/examples/selectvpc/main.tf
index 05bcf9b..6ad4529 100644
--- a/examples/selectvpc/main.tf
+++ b/examples/selectvpc/main.tf
@@ -22,7 +22,7 @@ locals {
 module "setup" {
   source              = "../../"
   vpc_name            = "${local.project_name}-vpc"
-  vpc_cidr            = "10.0.255.0/24"
+  vpc_cidr            = "10.0.0.0/16"
   subnet_use_strategy = "skip"
 }
 
diff --git a/main.tf b/main.tf
index 36b6aff..21f6214 100644
--- a/main.tf
+++ b/main.tf
@@ -47,11 +47,18 @@ locals {
   vpc_cidr = var.vpc_cidr
 
   # subnet
-  subnets                    = var.subnets
-  subnet_names               = keys(local.subnets)
-  subnet_count               = length(local.subnets)
-  newbits                    = (local.subnet_count > 1 ? ceil(log(local.subnet_count, 2)) : 1)
-  vpc_cidr_split             = [for i in range(local.subnet_count) : cidrsubnet(local.vpc_cidr, local.newbits, i)]
+  subnets      = var.subnets
+  subnet_names = keys(local.subnets)
+  subnet_count = length(local.subnets)
+  newbits      = (local.subnet_count > 1 ? ceil(log(local.subnet_count, 2)) : 1)
+  vpc_cidr_split = [
+    for i in range(local.subnet_count) :
+    cidrsubnet(
+      (local.vpc_mod == 1 ? module.vpc[0].cidr : local.vpc_cidr),
+      local.newbits,
+      i
+    )
+  ]
   potential_regional_subnets = { for i in range(local.subnet_count) : local.subnet_names[i] => local.vpc_cidr_split[i] }
 
   zones                  = tolist(data.aws_availability_zones.available.names)
diff --git a/modules/vpc/outputs.tf b/modules/vpc/outputs.tf
index c0b48f1..33770ca 100644
--- a/modules/vpc/outputs.tf
+++ b/modules/vpc/outputs.tf
@@ -3,4 +3,7 @@ output "id" {
 }
 output "vpc" {
   value = (local.select == 1 ? data.aws_vpc.selected[0] : aws_vpc.new[0])
-}
\ No newline at end of file
+}
+output "cidr" {
+  value = (local.select == 1 ? data.aws_vpc.selected[0].cidr_block : aws_vpc.new[0].cidr_block)
+}