diff --git a/x-pack/legacy/plugins/ml/common/util/validators.test.ts b/x-pack/legacy/plugins/ml/common/util/validators.test.ts
index 8b55e955a39539..7a8b28c14a4a4d 100644
--- a/x-pack/legacy/plugins/ml/common/util/validators.test.ts
+++ b/x-pack/legacy/plugins/ml/common/util/validators.test.ts
@@ -4,7 +4,7 @@
  * you may not use this file except in compliance with the Elastic License.
  */
 
-import { maxLengthValidator } from './validators';
+import { maxLengthValidator, memoryInputValidator } from './validators';
 
 describe('maxLengthValidator', () => {
   test('should allow a valid input', () => {
@@ -20,3 +20,29 @@ describe('maxLengthValidator', () => {
     });
   });
 });
+
+describe('memoryInputValidator', () => {
+  test('should detect missing units', () => {
+    expect(memoryInputValidator()('10')).toEqual({
+      invalidUnits: {
+        allowedUnits: 'B, KB, MB, GB, TB, PB',
+      },
+    });
+  });
+
+  test('should accept valid input', () => {
+    expect(memoryInputValidator()('100PB')).toEqual(null);
+  });
+
+  test('should accept valid input with custom allowed units', () => {
+    expect(memoryInputValidator(['B', 'KB'])('100KB')).toEqual(null);
+  });
+
+  test('should detect not allowed units', () => {
+    expect(memoryInputValidator(['B', 'KB'])('100MB')).toEqual({
+      invalidUnits: {
+        allowedUnits: 'B, KB',
+      },
+    });
+  });
+});
diff --git a/x-pack/legacy/plugins/ml/common/util/validators.ts b/x-pack/legacy/plugins/ml/common/util/validators.ts
index 7e0dd624a52e0c..304d9a0029540a 100644
--- a/x-pack/legacy/plugins/ml/common/util/validators.ts
+++ b/x-pack/legacy/plugins/ml/common/util/validators.ts
@@ -4,6 +4,8 @@
  * you may not use this file except in compliance with the Elastic License.
  */
 
+import { ALLOWED_DATA_UNITS } from '../constants/validation';
+
 /**
  * Provides a validator function for maximum allowed input length.
  * @param maxLength Maximum length allowed.
@@ -44,8 +46,8 @@ export function patternValidator(
  * @param validators
  */
 export function composeValidators(
-  ...validators: Array<(value: string) => { [key: string]: any } | null>
-): (value: string) => { [key: string]: any } | null {
+  ...validators: Array<(value: any) => { [key: string]: any } | null>
+): (value: any) => { [key: string]: any } | null {
   return value => {
     const validationResult = validators.reduce((acc, validator) => {
       return {
@@ -56,3 +58,21 @@ export function composeValidators(
     return Object.keys(validationResult).length > 0 ? validationResult : null;
   };
 }
+
+export function requiredValidator() {
+  return (value: any) => {
+    return value === '' || value === undefined || value === null ? { required: true } : null;
+  };
+}
+
+export function memoryInputValidator(allowedUnits = ALLOWED_DATA_UNITS) {
+  return (value: any) => {
+    if (typeof value !== 'string' || value === '') {
+      return null;
+    }
+    const regexp = new RegExp(`\\d+(${allowedUnits.join('|')})$`, 'i');
+    return regexp.test(value.trim())
+      ? null
+      : { invalidUnits: { allowedUnits: allowedUnits.join(', ') } };
+  };
+}
diff --git a/x-pack/legacy/plugins/ml/public/application/data_frame_analytics/pages/analytics_management/components/create_analytics_form/create_analytics_form.tsx b/x-pack/legacy/plugins/ml/public/application/data_frame_analytics/pages/analytics_management/components/create_analytics_form/create_analytics_form.tsx
index 338fa1e4ac328f..70722d9cb953a9 100644
--- a/x-pack/legacy/plugins/ml/public/application/data_frame_analytics/pages/analytics_management/components/create_analytics_form/create_analytics_form.tsx
+++ b/x-pack/legacy/plugins/ml/public/application/data_frame_analytics/pages/analytics_management/components/create_analytics_form/create_analytics_form.tsx
@@ -4,7 +4,7 @@
  * you may not use this file except in compliance with the Elastic License.
  */
 
-import React, { Fragment, FC, useEffect } from 'react';
+import React, { Fragment, FC, useEffect, useMemo } from 'react';
 
 import {
   EuiComboBox,
@@ -36,7 +36,7 @@ import { JOB_ID_MAX_LENGTH } from '../../../../../../../common/constants/validat
 import { Messages } from './messages';
 import { JobType } from './job_type';
 import { JobDescriptionInput } from './job_description';
-import { mmlUnitInvalidErrorMessage } from '../../hooks/use_create_analytics_form/reducer';
+import { getModelMemoryLimitErrors } from '../../hooks/use_create_analytics_form/reducer';
 import {
   IndexPattern,
   indexPatterns,
@@ -49,7 +49,7 @@ export const CreateAnalyticsForm: FC<CreateAnalyticsFormProps> = ({ actions, sta
     services: { docLinks },
   } = useMlKibana();
   const { ELASTIC_WEBSITE_URL, DOC_LINK_VERSION } = docLinks;
-  const { setFormState } = actions;
+  const { setFormState, setEstimatedModelMemoryLimit } = actions;
   const mlContext = useMlContext();
   const { form, indexPatternsMap, isAdvancedEditorEnabled, isJobCreated, requestMessages } = state;
 
@@ -77,7 +77,7 @@ export const CreateAnalyticsForm: FC<CreateAnalyticsFormProps> = ({ actions, sta
     loadingFieldOptions,
     maxDistinctValuesError,
     modelMemoryLimit,
-    modelMemoryLimitUnitValid,
+    modelMemoryLimitValidationResult,
     previousJobType,
     previousSourceIndex,
     sourceIndex,
@@ -89,6 +89,10 @@ export const CreateAnalyticsForm: FC<CreateAnalyticsFormProps> = ({ actions, sta
   } = form;
   const characterList = indexPatterns.ILLEGAL_CHARACTERS_VISIBLE.join(', ');
 
+  const mmlErrors = useMemo(() => getModelMemoryLimitErrors(modelMemoryLimitValidationResult), [
+    modelMemoryLimitValidationResult,
+  ]);
+
   const isJobTypeWithDepVar =
     jobType === JOB_TYPES.REGRESSION || jobType === JOB_TYPES.CLASSIFICATION;
 
@@ -154,6 +158,9 @@ export const CreateAnalyticsForm: FC<CreateAnalyticsFormProps> = ({ actions, sta
       const resp: DfAnalyticsExplainResponse = await ml.dataFrameAnalytics.explainDataFrameAnalytics(
         jobConfig
       );
+      const expectedMemoryWithoutDisk = resp.memory_estimation?.expected_memory_without_disk;
+
+      setEstimatedModelMemoryLimit(expectedMemoryWithoutDisk);
 
       // If sourceIndex has changed load analysis field options again
       if (previousSourceIndex !== sourceIndex || previousJobType !== jobType) {
@@ -168,7 +175,7 @@ export const CreateAnalyticsForm: FC<CreateAnalyticsFormProps> = ({ actions, sta
         }
 
         setFormState({
-          modelMemoryLimit: resp.memory_estimation?.expected_memory_without_disk,
+          ...(!modelMemoryLimit ? { modelMemoryLimit: expectedMemoryWithoutDisk } : {}),
           excludesOptions: analyzedFieldsOptions,
           loadingFieldOptions: false,
           fieldOptionsFetchFail: false,
@@ -176,7 +183,7 @@ export const CreateAnalyticsForm: FC<CreateAnalyticsFormProps> = ({ actions, sta
         });
       } else {
         setFormState({
-          modelMemoryLimit: resp.memory_estimation?.expected_memory_without_disk,
+          ...(!modelMemoryLimit ? { modelMemoryLimit: expectedMemoryWithoutDisk } : {}),
         });
       }
     } catch (e) {
@@ -189,14 +196,16 @@ export const CreateAnalyticsForm: FC<CreateAnalyticsFormProps> = ({ actions, sta
       ) {
         errorMessage = e.message;
       }
+      const fallbackModelMemoryLimit =
+        jobType !== undefined
+          ? DEFAULT_MODEL_MEMORY_LIMIT[jobType]
+          : DEFAULT_MODEL_MEMORY_LIMIT.outlier_detection;
+      setEstimatedModelMemoryLimit(fallbackModelMemoryLimit);
       setFormState({
         fieldOptionsFetchFail: true,
         maxDistinctValuesError: errorMessage,
         loadingFieldOptions: false,
-        modelMemoryLimit:
-          jobType !== undefined
-            ? DEFAULT_MODEL_MEMORY_LIMIT[jobType]
-            : DEFAULT_MODEL_MEMORY_LIMIT.outlier_detection,
+        modelMemoryLimit: fallbackModelMemoryLimit,
       });
     }
   }, 400);
@@ -642,7 +651,8 @@ export const CreateAnalyticsForm: FC<CreateAnalyticsFormProps> = ({ actions, sta
             label={i18n.translate('xpack.ml.dataframe.analytics.create.modelMemoryLimitLabel', {
               defaultMessage: 'Model memory limit',
             })}
-            helpText={!modelMemoryLimitUnitValid && mmlUnitInvalidErrorMessage}
+            isInvalid={modelMemoryLimitValidationResult !== null}
+            error={mmlErrors}
           >
             <EuiFieldText
               placeholder={
@@ -653,7 +663,7 @@ export const CreateAnalyticsForm: FC<CreateAnalyticsFormProps> = ({ actions, sta
               disabled={isJobCreated}
               value={modelMemoryLimit || ''}
               onChange={e => setFormState({ modelMemoryLimit: e.target.value })}
-              isInvalid={modelMemoryLimit === ''}
+              isInvalid={modelMemoryLimitValidationResult !== null}
               data-test-subj="mlAnalyticsCreateJobFlyoutModelMemoryInput"
             />
           </EuiFormRow>
diff --git a/x-pack/legacy/plugins/ml/public/application/data_frame_analytics/pages/analytics_management/hooks/use_create_analytics_form/actions.ts b/x-pack/legacy/plugins/ml/public/application/data_frame_analytics/pages/analytics_management/hooks/use_create_analytics_form/actions.ts
index a763bd9639bf3e..70228f0238fda0 100644
--- a/x-pack/legacy/plugins/ml/public/application/data_frame_analytics/pages/analytics_management/hooks/use_create_analytics_form/actions.ts
+++ b/x-pack/legacy/plugins/ml/public/application/data_frame_analytics/pages/analytics_management/hooks/use_create_analytics_form/actions.ts
@@ -24,6 +24,7 @@ export enum ACTION {
   SET_JOB_CONFIG,
   SET_JOB_IDS,
   SWITCH_TO_ADVANCED_EDITOR,
+  SET_ESTIMATED_MODEL_MEMORY_LIMIT,
 }
 
 export type Action =
@@ -59,7 +60,8 @@ export type Action =
     }
   | { type: ACTION.SET_IS_MODAL_VISIBLE; isModalVisible: State['isModalVisible'] }
   | { type: ACTION.SET_JOB_CONFIG; payload: State['jobConfig'] }
-  | { type: ACTION.SET_JOB_IDS; jobIds: State['jobIds'] };
+  | { type: ACTION.SET_JOB_IDS; jobIds: State['jobIds'] }
+  | { type: ACTION.SET_ESTIMATED_MODEL_MEMORY_LIMIT; value: State['estimatedModelMemoryLimit'] };
 
 // Actions wrapping the dispatcher exposed by the custom hook
 export interface ActionDispatchers {
@@ -73,4 +75,5 @@ export interface ActionDispatchers {
   setJobConfig: (payload: State['jobConfig']) => void;
   startAnalyticsJob: () => void;
   switchToAdvancedEditor: () => void;
+  setEstimatedModelMemoryLimit: (value: State['estimatedModelMemoryLimit']) => void;
 }
diff --git a/x-pack/legacy/plugins/ml/public/application/data_frame_analytics/pages/analytics_management/hooks/use_create_analytics_form/reducer.test.ts b/x-pack/legacy/plugins/ml/public/application/data_frame_analytics/pages/analytics_management/hooks/use_create_analytics_form/reducer.test.ts
index 7ea2f74908e0e2..5c989f7248a9eb 100644
--- a/x-pack/legacy/plugins/ml/public/application/data_frame_analytics/pages/analytics_management/hooks/use_create_analytics_form/reducer.test.ts
+++ b/x-pack/legacy/plugins/ml/public/application/data_frame_analytics/pages/analytics_management/hooks/use_create_analytics_form/reducer.test.ts
@@ -9,7 +9,7 @@ import { merge } from 'lodash';
 import { DataFrameAnalyticsConfig } from '../../../../common';
 
 import { ACTION } from './actions';
-import { reducer, validateAdvancedEditor } from './reducer';
+import { reducer, validateAdvancedEditor, validateMinMML } from './reducer';
 import { getInitialState, JOB_TYPES } from './state';
 
 type SourceIndex = DataFrameAnalyticsConfig['source']['index'];
@@ -41,13 +41,19 @@ describe('useCreateAnalyticsForm', () => {
     const initialState = getInitialState();
     expect(initialState.isValid).toBe(false);
 
-    const updatedState = reducer(initialState, {
+    const stateWithEstimatedMml = reducer(initialState, {
+      type: ACTION.SET_ESTIMATED_MODEL_MEMORY_LIMIT,
+      value: '182222kb',
+    });
+
+    const updatedState = reducer(stateWithEstimatedMml, {
       type: ACTION.SET_FORM_STATE,
       payload: {
         destinationIndex: 'the-destination-index',
         jobId: 'the-analytics-job-id',
         sourceIndex: 'the-source-index',
         jobType: JOB_TYPES.OUTLIER_DETECTION,
+        modelMemoryLimit: '200mb',
       },
     });
     expect(updatedState.isValid).toBe(true);
@@ -146,3 +152,23 @@ describe('useCreateAnalyticsForm', () => {
     ).toBe(false);
   });
 });
+
+describe('validateMinMML', () => {
+  test('should detect a lower value', () => {
+    expect(validateMinMML('10mb')('100kb')).toEqual({
+      min: { minValue: '10mb', actualValue: '100kb' },
+    });
+  });
+
+  test('should allow a bigger value', () => {
+    expect(validateMinMML('10mb')('1GB')).toEqual(null);
+  });
+
+  test('should allow the same value', () => {
+    expect(validateMinMML('1024mb')('1gb')).toEqual(null);
+  });
+
+  test('should ignore empty parameters', () => {
+    expect(validateMinMML((undefined as unknown) as string)('')).toEqual(null);
+  });
+});
diff --git a/x-pack/legacy/plugins/ml/public/application/data_frame_analytics/pages/analytics_management/hooks/use_create_analytics_form/reducer.ts b/x-pack/legacy/plugins/ml/public/application/data_frame_analytics/pages/analytics_management/hooks/use_create_analytics_form/reducer.ts
index f35fa6aa2f451c..42c2413607570c 100644
--- a/x-pack/legacy/plugins/ml/public/application/data_frame_analytics/pages/analytics_management/hooks/use_create_analytics_form/reducer.ts
+++ b/x-pack/legacy/plugins/ml/public/application/data_frame_analytics/pages/analytics_management/hooks/use_create_analytics_form/reducer.ts
@@ -5,6 +5,9 @@
  */
 
 import { i18n } from '@kbn/i18n';
+import { memoize } from 'lodash';
+// @ts-ignore
+import numeral from '@elastic/numeral';
 import { isValidIndexName } from '../../../../../../../common/util/es_utils';
 
 import { Action, ACTION } from './actions';
@@ -13,7 +16,12 @@ import {
   isJobIdValid,
   validateModelMemoryLimitUnits,
 } from '../../../../../../../common/util/job_utils';
-import { maxLengthValidator } from '../../../../../../../common/util/validators';
+import {
+  composeValidators,
+  maxLengthValidator,
+  memoryInputValidator,
+  requiredValidator,
+} from '../../../../../../../common/util/validators';
 import {
   JOB_ID_MAX_LENGTH,
   ALLOWED_DATA_UNITS,
@@ -37,6 +45,38 @@ export const mmlUnitInvalidErrorMessage = i18n.translate(
   }
 );
 
+/**
+ * Returns the list of model memory limit errors based on validation result.
+ * @param mmlValidationResult
+ */
+export function getModelMemoryLimitErrors(mmlValidationResult: any): string[] | null {
+  if (mmlValidationResult === null) {
+    return null;
+  }
+
+  return Object.keys(mmlValidationResult).reduce((acc, errorKey) => {
+    if (errorKey === 'min') {
+      acc.push(
+        i18n.translate('xpack.ml.dataframe.analytics.create.modelMemoryUnitsMinError', {
+          defaultMessage: 'Model memory limit cannot be lower than {mml}',
+          values: {
+            mml: mmlValidationResult.min.minValue,
+          },
+        })
+      );
+    }
+    if (errorKey === 'invalidUnits') {
+      acc.push(
+        i18n.translate('xpack.ml.dataframe.analytics.create.modelMemoryUnitsInvalidError', {
+          defaultMessage: 'Model memory limit data unit unrecognized. It must be {str}',
+          values: { str: mmlAllowedUnitsStr },
+        })
+      );
+    }
+    return acc;
+  }, [] as string[]);
+}
+
 const getSourceIndexString = (state: State) => {
   const { jobConfig } = state;
 
@@ -222,6 +262,39 @@ export const validateAdvancedEditor = (state: State): State => {
   return state;
 };
 
+/**
+ * Validates provided MML isn't lower than the estimated one.
+ */
+export function validateMinMML(estimatedMml: string) {
+  return (mml: string) => {
+    if (!mml || !estimatedMml) {
+      return null;
+    }
+
+    // @ts-ignore
+    const mmlInBytes = numeral(mml.toUpperCase()).value();
+    // @ts-ignore
+    const estimatedMmlInBytes = numeral(estimatedMml.toUpperCase()).value();
+
+    return estimatedMmlInBytes > mmlInBytes
+      ? { min: { minValue: estimatedMml, actualValue: mml } }
+      : null;
+  };
+}
+
+/**
+ * Result validator function for the MML.
+ * Re-init only if the estimated mml has been changed.
+ */
+const mmlValidator = memoize((estimatedMml: string) =>
+  composeValidators(requiredValidator(), validateMinMML(estimatedMml), memoryInputValidator())
+);
+
+const validateMml = memoize(
+  (estimatedMml: string, mml: string | undefined) => mmlValidator(estimatedMml)(mml),
+  (...args: any) => args.join('_')
+);
+
 const validateForm = (state: State): State => {
   const {
     jobIdEmpty,
@@ -238,22 +311,21 @@ const validateForm = (state: State): State => {
     maxDistinctValuesError,
     modelMemoryLimit,
   } = state.form;
+  const { estimatedModelMemoryLimit } = state;
 
   const jobTypeEmpty = jobType === undefined;
   const dependentVariableEmpty =
     (jobType === JOB_TYPES.REGRESSION || jobType === JOB_TYPES.CLASSIFICATION) &&
     dependentVariable === '';
-  const modelMemoryLimitEmpty = modelMemoryLimit === '';
 
-  if (!modelMemoryLimitEmpty && modelMemoryLimit !== undefined) {
-    const { valid } = validateModelMemoryLimitUnits(modelMemoryLimit);
-    state.form.modelMemoryLimitUnitValid = valid;
-  }
+  const mmlValidationResult = validateMml(estimatedModelMemoryLimit, modelMemoryLimit);
+
+  state.form.modelMemoryLimitValidationResult = mmlValidationResult;
 
   state.isValid =
     maxDistinctValuesError === undefined &&
     !jobTypeEmpty &&
-    state.form.modelMemoryLimitUnitValid &&
+    !mmlValidationResult &&
     !jobIdEmpty &&
     jobIdValid &&
     !jobIdExists &&
@@ -262,7 +334,6 @@ const validateForm = (state: State): State => {
     !destinationIndexNameEmpty &&
     destinationIndexNameValid &&
     !dependentVariableEmpty &&
-    !modelMemoryLimitEmpty &&
     (!destinationIndexPatternTitleExists || !createIndexPattern);
 
   return state;
@@ -373,6 +444,12 @@ export function reducer(state: State, action: Action): State {
         isAdvancedEditorEnabled: true,
         jobConfig,
       });
+
+    case ACTION.SET_ESTIMATED_MODEL_MEMORY_LIMIT:
+      return {
+        ...state,
+        estimatedModelMemoryLimit: action.value,
+      };
   }
 
   return state;
diff --git a/x-pack/legacy/plugins/ml/public/application/data_frame_analytics/pages/analytics_management/hooks/use_create_analytics_form/state.ts b/x-pack/legacy/plugins/ml/public/application/data_frame_analytics/pages/analytics_management/hooks/use_create_analytics_form/state.ts
index 282f9ff45d0ee0..1f23048e09d1f7 100644
--- a/x-pack/legacy/plugins/ml/public/application/data_frame_analytics/pages/analytics_management/hooks/use_create_analytics_form/state.ts
+++ b/x-pack/legacy/plugins/ml/public/application/data_frame_analytics/pages/analytics_management/hooks/use_create_analytics_form/state.ts
@@ -67,6 +67,7 @@ export interface State {
     maxDistinctValuesError: string | undefined;
     modelMemoryLimit: string | undefined;
     modelMemoryLimitUnitValid: boolean;
+    modelMemoryLimitValidationResult: any;
     previousJobType: null | AnalyticsJobType;
     previousSourceIndex: EsIndexName | undefined;
     sourceIndex: EsIndexName;
@@ -88,6 +89,7 @@ export interface State {
   jobConfig: DeepPartial<DataFrameAnalyticsConfig>;
   jobIds: DataFrameAnalyticsId[];
   requestMessages: FormMessage[];
+  estimatedModelMemoryLimit: string;
 }
 
 export const getInitialState = (): State => ({
@@ -118,6 +120,7 @@ export const getInitialState = (): State => ({
     maxDistinctValuesError: undefined,
     modelMemoryLimit: undefined,
     modelMemoryLimitUnitValid: true,
+    modelMemoryLimitValidationResult: null,
     previousJobType: null,
     previousSourceIndex: undefined,
     sourceIndex: '',
@@ -142,6 +145,7 @@ export const getInitialState = (): State => ({
   isValid: false,
   jobIds: [],
   requestMessages: [],
+  estimatedModelMemoryLimit: '',
 });
 
 export const getJobConfigFromFormState = (
diff --git a/x-pack/legacy/plugins/ml/public/application/data_frame_analytics/pages/analytics_management/hooks/use_create_analytics_form/use_create_analytics_form.ts b/x-pack/legacy/plugins/ml/public/application/data_frame_analytics/pages/analytics_management/hooks/use_create_analytics_form/use_create_analytics_form.ts
index 59474b63213a2b..350b3f98d46731 100644
--- a/x-pack/legacy/plugins/ml/public/application/data_frame_analytics/pages/analytics_management/hooks/use_create_analytics_form/use_create_analytics_form.ts
+++ b/x-pack/legacy/plugins/ml/public/application/data_frame_analytics/pages/analytics_management/hooks/use_create_analytics_form/use_create_analytics_form.ts
@@ -297,6 +297,10 @@ export const useCreateAnalyticsForm = (): CreateAnalyticsFormProps => {
     dispatch({ type: ACTION.SWITCH_TO_ADVANCED_EDITOR });
   };
 
+  const setEstimatedModelMemoryLimit = (value: State['estimatedModelMemoryLimit']) => {
+    dispatch({ type: ACTION.SET_ESTIMATED_MODEL_MEMORY_LIMIT, value });
+  };
+
   const actions: ActionDispatchers = {
     closeModal,
     createAnalyticsJob,
@@ -308,6 +312,7 @@ export const useCreateAnalyticsForm = (): CreateAnalyticsFormProps => {
     setJobConfig,
     startAnalyticsJob,
     switchToAdvancedEditor,
+    setEstimatedModelMemoryLimit,
   };
 
   return { state, actions };