diff --git a/src/components/DropZone.tsx b/src/components/DropZone.tsx
index c5784e60..52c7c9f9 100644
--- a/src/components/DropZone.tsx
+++ b/src/components/DropZone.tsx
@@ -1,6 +1,6 @@
 import { Box, Button, Text, useTheme, useToast } from "@chakra-ui/react"
 import { useDropzone } from "react-dropzone"
-import XLSX from "xlsx"
+import * as XLSX from "xlsx"
 import { useState } from "react"
 import { getDropZoneBorder } from "../utils/getDropZoneBorder"
 
diff --git a/src/components/EditableTable.tsx b/src/components/EditableTable.tsx
index 37565104..f9ce799c 100644
--- a/src/components/EditableTable.tsx
+++ b/src/components/EditableTable.tsx
@@ -22,11 +22,6 @@ const createGlobalStyleOverride = () => css`
     --rdg-selection-color: none;
   }
 
-  .rdg-header-row .rdg-cell {
-    --rdg-selection-color: none;
-    border: none;
-  }
-
   .rdg-checkbox {
     --rdg-selection-color: none;
     background-color: var(--rdg-header-background-color);
@@ -51,7 +46,6 @@ const createGlobalStyleOverride = () => css`
   }
 
   .rdg-cell[aria-selected="true"] {
-    border-radius: 2px;
     box-shadow: inset 0 0 0 1px var(--rdg-selection-color);
   }
 
@@ -59,6 +53,14 @@ const createGlobalStyleOverride = () => css`
     background-color: var(--chakra-colors-red-50);
     box-shadow: inset 0 0 0 1px var(--chakra-colors-red-100);
   }
+  .rdg-cell-warning {
+    background-color: var(--chakra-colors-orange-50);
+    box-shadow: 0 1px 0 0 var(--chakra-colors-orange-100);
+  }
+  .rdg-cell-info {
+    background-color: var(--chakra-colors-blue-50);
+    box-shadow: inset 0 0 0 1px var(--chakra-colors-blue-100);
+  }
 
   .rdg {
     contain: size layout style paint;
@@ -74,7 +76,7 @@ const createGlobalStyleOverride = () => css`
     --rdg-font-size: 14px;
   }
 `
-const ROW_HEIGHT = 42
+const ROW_HEIGHT = 35
 
 interface Props<Data> extends DataGridProps<Data> {
   rowHeight?: number
diff --git a/src/stories/Table.stories.tsx b/src/stories/Table.stories.tsx
index 36437ad2..22765fba 100644
--- a/src/stories/Table.stories.tsx
+++ b/src/stories/Table.stories.tsx
@@ -1,16 +1,19 @@
 import { Box, ChakraProvider, Checkbox, extendTheme, Input, Select, Switch } from "@chakra-ui/react"
 import { EditableTable } from "../components/EditableTable"
-import { connect, useLape } from "lape"
+import { connect, ignoreState, useLape } from "lape"
 import type { ChangeEvent } from "react"
 import { colorSchemeOverrides, themeOverrides } from "../theme"
-import type { Field, Fields } from "../types"
+import type { Field, Fields, Info } from "../types"
 import type { Column, FormatterProps } from "react-data-grid"
 import { useRowSelection } from "react-data-grid"
 export default {
   title: "React spreadsheet import",
 }
 
-export const SELECT_COLUMN_KEY = "select-row"
+type Errors = { [id: string]: { [key: string]: Info } }
+type Data = { [key: string]: string | number | boolean | null }[]
+
+const SELECT_COLUMN_KEY = "select-row"
 
 function SelectFormatter(props: FormatterProps<unknown>) {
   const [isRowSelected, onRowSelectionChange] = useRowSelection()
@@ -48,26 +51,22 @@ const theme = extendTheme(colorSchemeOverrides, themeOverrides)
 const TableComponent = connect(() => {
   const data = [
     {
-      id: 0,
       test: "Hello",
       second: "one",
       bool: true,
     },
     {
-      id: 1,
-      test: "Hello",
+      test: "123123",
       second: "two",
       bool: true,
     },
     {
-      id: 2,
-      test: "Hello",
-      second: "one",
+      test: "123123",
+      second: null,
       bool: false,
     },
     {
-      id: 3,
-      test: "Hello",
+      test: "111",
       second: "two",
       bool: true,
     },
@@ -78,6 +77,19 @@ const TableComponent = connect(() => {
       key: "test",
       label: "Tests",
       fieldType: { type: "input" },
+      validations: [
+        {
+          rule: "unique",
+          errorMessage: "Test must be unique",
+          level: "info",
+        },
+        {
+          rule: "regex",
+          value: "^\\d+$",
+          errorMessage: "Test must be number",
+          level: "warning",
+        },
+      ],
     },
     {
       key: "second",
@@ -89,6 +101,12 @@ const TableComponent = connect(() => {
           { label: "Two", value: "two" },
         ],
       },
+      validations: [
+        {
+          rule: "required",
+          errorMessage: "Second is required",
+        },
+      ],
     },
     {
       key: "bool",
@@ -97,25 +115,81 @@ const TableComponent = connect(() => {
     },
   ]
 
+  const runValidation = (data: Data): Errors => {
+    let errors: Errors = {}
+    fields.forEach((field) => {
+      field.validations?.forEach((validation) => {
+        switch (validation.rule) {
+          case "unique": {
+            const values = data.map((entry) => entry[field.key])
+            values.forEach((value, index) => {
+              if (values.indexOf(value) !== values.lastIndexOf(value)) {
+                errors[index] = {
+                  ...errors[index],
+                  [field.key]: {
+                    level: validation.level || "error",
+                    message: validation.errorMessage || "Field must be unique",
+                  },
+                }
+              }
+            })
+            break
+          }
+          case "required": {
+            data.forEach((entry, index) => {
+              if (entry[field.key] === null || entry[field.key] === undefined || entry[field.key] === "") {
+                errors[index] = {
+                  ...errors[index],
+                  [field.key]: {
+                    level: validation.level || "error",
+                    message: validation.errorMessage || "Field is required",
+                  },
+                }
+              }
+            })
+            break
+          }
+          case "regex": {
+            const regex = new RegExp(validation.value, validation.flags)
+            data.forEach((entry, index) => {
+              if (!entry[field.key]?.toString()?.match(regex)) {
+                errors[index] = {
+                  ...errors[index],
+                  [field.key]: {
+                    level: validation.level || "error",
+                    message:
+                      validation.errorMessage ||
+                      `Field did not match the regex /${validation.value}/${validation.flags} `,
+                  },
+                }
+              }
+            })
+            break
+          }
+        }
+      })
+    })
+    return errors
+  }
+
   const state = useLape<{
-    data: any[]
+    data: Data
     errorCount: number
     filterErrors: boolean
+    errors: Errors
     selectedRows: ReadonlySet<number | string>
   }>({
-    data: data,
+    data: ignoreState(data),
     errorCount: 0,
+    errors: runValidation(data),
     filterErrors: false,
     selectedRows: new Set(),
   })
 
-  const updateSelect = (row: any, key: string) => (event: ChangeEvent<HTMLSelectElement>) => {
-    row[key] = event.target.value
-  }
-  const updateInput = (row: any, key: string) => (event: ChangeEvent<HTMLInputElement>) => {
-    row[key] = event.target.value
+  const updateRow = (rows: any[]) => {
+    state.data = rows
+    state.errors = runValidation(state.data)
   }
-  const updateSwitch = () => {}
   const columns = [
     SelectColumn,
     ...fields.map((column: Field) => ({
@@ -123,7 +197,7 @@ const TableComponent = connect(() => {
       name: column.label,
       resizable: true,
       editable: column.fieldType.type !== "checkbox",
-      editor: ({ row }: any) =>
+      editor: ({ row, onRowChange, onClose }: any) =>
         column.fieldType.type === "select" ? (
           <Box pl="0.5rem">
             <Select
@@ -131,7 +205,10 @@ const TableComponent = connect(() => {
               autoFocus
               size="small"
               value={row[column.key]}
-              onChange={updateSelect(row, column.key)}
+              onChange={(event: ChangeEvent<HTMLSelectElement>) => {
+                onRowChange({ ...row, [column.key]: event.target.value }, true)
+              }}
+              placeholder=" "
             >
               {column.fieldType.options.map((option) => (
                 <option value={option.value}>{option.label}</option>
@@ -145,32 +222,59 @@ const TableComponent = connect(() => {
               autoFocus
               size="small"
               value={row[column.key]}
-              onChange={updateInput(row, column.key)}
+              onChange={(event: ChangeEvent<HTMLInputElement>) => {
+                onRowChange({ ...row, [column.key]: event.target.value })
+              }}
+              onBlur={onClose}
             />
           </Box>
         ),
       editorOptions: {
         editOnClick: true,
       },
-      formatter: ({ row }: any) =>
+      formatter: ({ row, onRowChange }: any) =>
         column.fieldType.type === "checkbox" ? (
-          <Box display="flex" alignItems="center" height="100%">
-            <Switch onChange={updateSwitch} />
+          <Box
+            display="flex"
+            alignItems="center"
+            height="100%"
+            onClick={(event) => {
+              event.stopPropagation()
+            }}
+          >
+            <Switch
+              isChecked={row[column.key]}
+              onChange={() => {
+                onRowChange({ ...row, [column.key]: !row[column.key] }, true)
+              }}
+            />
           </Box>
         ) : column.fieldType.type === "select" ? (
-          column.fieldType.options.find((option) => option.value === row[column.key])?.label
+          column.fieldType.options.find((option) => option.value === row[column.key])?.label || null
         ) : (
           row[column.key]
         ),
-      cellClass: (row: { _errors: any[] | null; id: string }) =>
-        row._errors?.length && row._errors.find((err) => err.fieldName === column.key) ? "rdg-cell-error" : "",
+      cellClass: (row: any) => {
+        const index = state.data.indexOf(row)
+        switch (state.errors[index]?.[column.key]?.level) {
+          case "error":
+            return "rdg-cell-error"
+          case "warning":
+            return "rdg-cell-warning"
+          case "info":
+            return "rdg-cell-info"
+          default:
+            return ""
+        }
+      },
     })),
   ]
 
   return (
     <EditableTable
-      rowKeyGetter={(row) => row.id}
+      rowKeyGetter={(row) => state.data.indexOf(row)}
       rows={state.data}
+      onRowsChange={updateRow}
       columns={columns}
       selectedRows={state.selectedRows}
       onSelectedRowsChange={(rows) => {
diff --git a/src/types.ts b/src/types.ts
index 86596f8c..7e8f2ea1 100644
--- a/src/types.ts
+++ b/src/types.ts
@@ -39,13 +39,13 @@ export type Field = {
 }
 
 export type Checkbox = {
-  type: 'checkbox'
+  type: "checkbox"
   // Alternate values to be treated as booleans, e.g. 'yes'-> true, 'no' -> false
-  booleanMatches?: {[key: string]: boolean}[]
+  booleanMatches?: { [key: string]: boolean }[]
 }
 
 export type Select = {
-  type : 'select'
+  type: "select"
   // Options displayed in Select component
   options: SelectOptions[]
 }
@@ -58,24 +58,25 @@ export type SelectOptions = {
 }
 
 export type Input = {
-  type: 'input'
+  type: "input"
 }
 
-export type Validation =  BasicValidation | RegexValidation
+export type Validation = BasicValidation | RegexValidation
 
 export type BasicValidation = {
-  rule: 'unique' | 'required' 	//... to be determined
+  rule: "unique" | "required" //... to be determined
   errorMessage?: string
+  level?: ErrorLevel
 }
 
 export type RegexValidation = {
-  rule: 'regex'
-  regexOptions?: RegexOption[]
+  rule: "regex"
+  value: string
+  flags?: string
   errorMessage: string
+  level?: ErrorLevel
 }
 
-export type RegexOption = 'i' | 'm' | 'u' | 's'
-
 export type Hooks = {
   // Runs after column matching and on entry change, more performant
   rowHooks: RowHook[]
@@ -85,7 +86,7 @@ export type Hooks = {
   initalHooks: TableHook[]
 }
 
-export type RowHook = ({...rowValues}: object) => Promise<Entry>
+export type RowHook = ({ ...rowValues }: object) => Promise<Entry>
 export type TableHook = (tableData: object[]) => Promise<Entry[]>
 
 export type Entry = {
@@ -93,9 +94,11 @@ export type Entry = {
   info: Info[]
 }
 
+export type ErrorLevel = "info" | "warning" | "error"
+
 export type Info = {
   message: string
-  level: 'info' | 'warning' | 'error'
+  level: ErrorLevel
 }
 
 export type Result = {
@@ -108,4 +111,4 @@ export type MaybeConfig = {
   allowInvalidSubmit?: boolean
   displayEncoding?: boolean
   allowCustomFields?: boolean
-}
\ No newline at end of file
+}