diff --git a/chain.go b/chain.go
index 05ae9ab..8268aa2 100644
--- a/chain.go
+++ b/chain.go
@@ -21,7 +21,7 @@ import (
 
 // SanitizeBlockForCompareFunc takes a chain agnostic [block] and transforms it in-place, removing fields
 // that should not be compared.
-type SanitizeBlockForCompareFunc[B Block] func(block B) B
+type SanitizeBlockForCompareFunc func(block *pbbstream.Block) *pbbstream.Block
 
 // Chain is the omni config object for configuring your chain specific information. It contains various
 // fields that are used everywhere to properly configure the `firehose-<chain>` binary.
@@ -154,6 +154,12 @@ type Chain[B Block] struct {
 }
 
 type ToolsConfig[B Block] struct {
+	// SanitizeBlockForCompare is a function that takes a chain agnostic [block] and transforms it in-place, removing fields
+	// that should not be compared.
+	//
+	// The [SanitizeBlockForCompare] is optional, if nil, no-op sanitizer be used.
+	SanitizeBlockForCompare SanitizeBlockForCompareFunc
+
 	// RegisterExtraCmd enables you to register extra commands to the `fire<chain> tools` group.
 	// The callback function is called with the `toolsCmd` command that is the root command of the `fire<chain> tools`
 	// as well as the chain, the root logger and root tracer for tools.
@@ -183,6 +189,15 @@ type ToolsConfig[B Block] struct {
 	MergedBlockUpgrader func(block *pbbstream.Block) (*pbbstream.Block, error)
 }
 
+// GetSanitizeBlockForCompare returns the [SanitizeBlockForCompare] value if defined, otherwise a no-op sanitizer.
+func (t *ToolsConfig[B]) GetSanitizeBlockForCompare() SanitizeBlockForCompareFunc {
+	if t == nil || t.SanitizeBlockForCompare == nil {
+		return func(block *pbbstream.Block) *pbbstream.Block { return block }
+	}
+
+	return t.SanitizeBlockForCompare
+}
+
 type TransformFlags struct {
 	// Register is a function that will be called when we need to register the flags for the transforms.
 	// You received the command's flag set and you are responsible of registering the flags.
diff --git a/cmd/tools/compare/tools_compare_blocks.go b/cmd/tools/compare/tools_compare_blocks.go
index 2211189..063a116 100644
--- a/cmd/tools/compare/tools_compare_blocks.go
+++ b/cmd/tools/compare/tools_compare_blocks.go
@@ -81,6 +81,7 @@ func NewToolsCompareBlocksCmd[B firecore.Block](chain *firecore.Chain[B]) *cobra
 }
 
 func runCompareBlocksE[B firecore.Block](chain *firecore.Chain[B]) firecore.CommandExecutor {
+
 	return func(cmd *cobra.Command, args []string) error {
 		displayDiff := sflags.MustGetBool(cmd, "diff")
 		includeUnknownFields := sflags.MustGetBool(cmd, "include-unknown-fields")
@@ -123,6 +124,8 @@ func runCompareBlocksE[B firecore.Block](chain *firecore.Chain[B]) firecore.Comm
 			return fmt.Errorf("creating registry: %w", err)
 		}
 
+		sanitizer := chain.Tools.GetSanitizeBlockForCompare()
+
 		err = storeReference.Walk(ctx, check.WalkBlockPrefix(blockRange, 100), func(filename string) (err error) {
 			fileStartBlock, err := strconv.Atoi(filename)
 			if err != nil {
@@ -153,6 +156,7 @@ func runCompareBlocksE[B firecore.Block](chain *firecore.Chain[B]) firecore.Comm
 						uint64(fileStartBlock),
 						stopBlock,
 						&warnAboutExtraBlocks,
+						sanitizer,
 						registry,
 					)
 					if err != nil {
@@ -171,6 +175,7 @@ func runCompareBlocksE[B firecore.Block](chain *firecore.Chain[B]) firecore.Comm
 						uint64(fileStartBlock),
 						stopBlock,
 						&warnAboutExtraBlocks,
+						sanitizer,
 						registry,
 					)
 					if err != nil {
@@ -234,6 +239,7 @@ func readBundle(
 	fileStartBlock,
 	stopBlock uint64,
 	warnAboutExtraBlocks *sync.Once,
+	sanitizer firecore.SanitizeBlockForCompareFunc,
 	registry *fcproto.Registry,
 ) ([]string, map[string]*dynamicpb.Message, map[string]uint64, error) {
 	fileReader, err := store.OpenObject(ctx, filename)
@@ -268,6 +274,10 @@ func readBundle(
 			continue
 		}
 
+		if sanitizer != nil {
+			curBlock = sanitizer(curBlock)
+		}
+
 		curBlockPB, err := registry.Unmarshal(curBlock.Payload)
 
 		if err != nil {