diff --git a/core/collection_model.go b/core/collection_model.go
index 6707a502..fe04e77c 100644
--- a/core/collection_model.go
+++ b/core/collection_model.go
@@ -3,8 +3,10 @@ package core
 import (
 	"encoding/json"
 	"fmt"
+	"strconv"
 	"strings"
 
+	"github.com/pocketbase/dbx"
 	"github.com/pocketbase/pocketbase/tools/dbutils"
 	"github.com/pocketbase/pocketbase/tools/hook"
 	"github.com/pocketbase/pocketbase/tools/security"
@@ -309,6 +311,7 @@ type baseCollection struct {
 	BaseModel
 
 	disableIntegrityChecks bool
+	autogeneratedId        string
 
 	ListRule   *string `db:"listRule" json:"listRule" form:"listRule"`
 	ViewRule   *string `db:"viewRule" json:"viewRule" form:"viewRule"`
@@ -364,6 +367,7 @@ func NewBaseCollection(name string, optId ...string) *Collection {
 	m.Name = name
 	m.Type = CollectionTypeBase
 
+	// @todo consider removing once inferred composite literals are supported
 	if len(optId) > 0 {
 		m.Id = optId[0]
 	}
@@ -383,6 +387,7 @@ func NewViewCollection(name string, optId ...string) *Collection {
 	m.Name = name
 	m.Type = CollectionTypeView
 
+	// @todo consider removing once inferred composite literals are supported
 	if len(optId) > 0 {
 		m.Id = optId[0]
 	}
@@ -402,6 +407,7 @@ func NewAuthCollection(name string, optId ...string) *Collection {
 	m.Name = name
 	m.Type = CollectionTypeAuth
 
+	// @todo consider removing once inferred composite literals are supported
 	if len(optId) > 0 {
 		m.Id = optId[0]
 	}
@@ -689,49 +695,82 @@ func onCollectionDeleteExecute(e *CollectionEvent) error {
 // save hook
 // -------------------------------------------------------------------
 
-func (c *Collection) initDefaultId() {
-	if c.Id != "" {
-		return // already set
-	}
+func (c *Collection) idChecksum() string {
+	return "pbc_" + crc32Checksum(c.Type+c.Name)
+}
 
-	if c.System && c.Name != "" {
-		// for system collections we use crc32 checksum for consistency because they cannot be renamed
-		c.Id = "pbc_" + crc32Checksum(c.Name)
-	} else {
-		c.Id = "pbc_" + security.RandomStringWithAlphabet(11, DefaultIdAlphabet)
+func (c *Collection) initDefaultId() {
+	if c.Id == "" {
+		c.Id = c.idChecksum()
+		c.autogeneratedId = c.Id
 	}
 }
 
-func (c *Collection) savePrepare() error {
-	if c.Type == "" {
-		c.Type = CollectionTypeBase
+func (c *Collection) updateGeneratedIdIfExists(app App) {
+	if !c.IsNew() ||
+		// the id was explicitly cleared
+		c.Id == "" ||
+		// the id was manually set
+		c.Id != c.autogeneratedId {
+		return
 	}
 
-	if c.IsNew() {
-		c.initDefaultId()
-		c.Created = types.NowDateTime()
+	// generate an up-to-date checksum
+	newId := c.idChecksum()
+
+	// add a number to the current id (if already exists)
+	for i := 2; i < 1000; i++ {
+		var exists bool
+		_ = app.CollectionQuery().Select("(1)").AndWhere(dbx.HashExp{"id": newId}).Limit(1).Row(&exists)
+		if !exists {
+			break
+		}
+		newId = c.idChecksum() + strconv.Itoa(i)
 	}
 
-	c.Updated = types.NowDateTime()
-
-	// recreate the fields list to ensure that all normalizations
-	// like default field id are applied
-	c.Fields = NewFieldsList(c.Fields...)
-
-	c.initDefaultFields()
-
-	if c.IsAuth() {
-		c.unsetMissingOAuth2MappedFields()
+	// no change
+	if c.Id == newId {
+		return
 	}
 
-	return nil
+	// replace the old id in the index names (if any)
+	for i, idx := range c.Indexes {
+		parsed := dbutils.ParseIndex(idx)
+		original := parsed.IndexName
+		parsed.IndexName = strings.ReplaceAll(parsed.IndexName, c.Id, newId)
+		if parsed.IndexName != original {
+			c.Indexes[i] = parsed.Build()
+		}
+	}
+
+	// update model id
+	c.Id = newId
 }
 
 func onCollectionSave(e *CollectionEvent) error {
-	if err := e.Collection.savePrepare(); err != nil {
-		return err
+	if e.Collection.Type == "" {
+		e.Collection.Type = CollectionTypeBase
 	}
 
+	if e.Collection.IsNew() {
+		e.Collection.initDefaultId()
+		e.Collection.Created = types.NowDateTime()
+	}
+
+	e.Collection.Updated = types.NowDateTime()
+
+	// recreate the fields list to ensure that all normalizations
+	// like default field id are applied
+	e.Collection.Fields = NewFieldsList(e.Collection.Fields...)
+
+	e.Collection.initDefaultFields()
+
+	if e.Collection.IsAuth() {
+		e.Collection.unsetMissingOAuth2MappedFields()
+	}
+
+	e.Collection.updateGeneratedIdIfExists(e.App)
+
 	return e.Next()
 }
 
diff --git a/core/collection_validate.go b/core/collection_validate.go
index 9699d089..875871bd 100644
--- a/core/collection_validate.go
+++ b/core/collection_validate.go
@@ -65,6 +65,10 @@ type optionsValidator interface {
 }
 
 func (validator *collectionValidator) run() error {
+	if validator.original.IsNew() {
+		validator.new.updateGeneratedIdIfExists(validator.app)
+	}
+
 	// generate fields from the query (overwriting any explicit user defined fields)
 	if validator.new.IsView() {
 		validator.new.Fields, _ = validator.app.CreateViewFields(validator.new.ViewQuery)
diff --git a/core/fields_list.go b/core/fields_list.go
index 5e640d8f..4f91c435 100644
--- a/core/fields_list.go
+++ b/core/fields_list.go
@@ -4,8 +4,7 @@ import (
 	"database/sql/driver"
 	"encoding/json"
 	"fmt"
-
-	"github.com/pocketbase/pocketbase/tools/security"
+	"strconv"
 )
 
 // NewFieldsList creates a new FieldsList instance with the provided fields.
@@ -171,12 +170,16 @@ func (l *FieldsList) add(newField Field) {
 	// set default id
 	if newFieldId == "" {
 		replaceByName = true
-		if newField.GetSystem() && newField.GetName() != "" {
-			// for system fields we use crc32 checksum for consistency because they cannot be renamed
-			newFieldId = newField.Type() + crc32Checksum(newField.GetName())
-		} else {
-			newFieldId = newField.Type() + security.RandomString(7)
+
+		baseId := newField.Type() + crc32Checksum(newField.GetName())
+		newFieldId = baseId
+		for i := 2; i < 1000; i++ {
+			if l.GetById(newFieldId) == nil {
+				break // already unique
+			}
+			newFieldId = baseId + strconv.Itoa(i)
 		}
+		newField.SetId(newFieldId)
 	}
 
 	// replace existing
@@ -196,7 +199,6 @@ func (l *FieldsList) add(newField Field) {
 	}
 
 	// add new field
-	newField.SetId(newFieldId)
 	*l = append(fields, newField)
 }