diff --git a/Documentation/git-commit-graph.txt b/Documentation/git-commit-graph.txt
index a222cfab08..dececb79d7 100644
--- a/Documentation/git-commit-graph.txt
+++ b/Documentation/git-commit-graph.txt
@@ -38,12 +38,16 @@ Write a commit graph file based on the commits found in packfiles.
 +
 With the `--stdin-packs` option, generate the new commit graph by
 walking objects only in the specified pack-indexes. (Cannot be combined
-with --stdin-commits.)
+with `--stdin-commits` or `--reachable`.)
 +
 With the `--stdin-commits` option, generate the new commit graph by
 walking commits starting at the commits specified in stdin as a list
 of OIDs in hex, one OID per line. (Cannot be combined with
---stdin-packs.)
+`--stdin-packs` or `--reachable`.)
++
+With the `--reachable` option, generate the new commit graph by walking
+commits starting at all refs. (Cannot be combined with `--stdin-commits`
+or `--stdin-packs`.)
 +
 With the `--append` option, include all commits that are present in the
 existing commit-graph file.
diff --git a/builtin/commit-graph.c b/builtin/commit-graph.c
index ea28bc311a..c7d0db5ab4 100644
--- a/builtin/commit-graph.c
+++ b/builtin/commit-graph.c
@@ -10,7 +10,7 @@ static char const * const builtin_commit_graph_usage[] = {
 	N_("git commit-graph [--object-dir <objdir>]"),
 	N_("git commit-graph read [--object-dir <objdir>]"),
 	N_("git commit-graph verify [--object-dir <objdir>]"),
-	N_("git commit-graph write [--object-dir <objdir>] [--append] [--stdin-packs|--stdin-commits]"),
+	N_("git commit-graph write [--object-dir <objdir>] [--append] [--reachable|--stdin-packs|--stdin-commits]"),
 	NULL
 };
 
@@ -25,12 +25,13 @@ static const char * const builtin_commit_graph_read_usage[] = {
 };
 
 static const char * const builtin_commit_graph_write_usage[] = {
-	N_("git commit-graph write [--object-dir <objdir>] [--append] [--stdin-packs|--stdin-commits]"),
+	N_("git commit-graph write [--object-dir <objdir>] [--append] [--reachable|--stdin-packs|--stdin-commits]"),
 	NULL
 };
 
 static struct opts_commit_graph {
 	const char *obj_dir;
+	int reachable;
 	int stdin_packs;
 	int stdin_commits;
 	int append;
@@ -127,6 +128,8 @@ static int graph_write(int argc, const char **argv)
 		OPT_STRING(0, "object-dir", &opts.obj_dir,
 			N_("dir"),
 			N_("The object directory to store the graph")),
+		OPT_BOOL(0, "reachable", &opts.reachable,
+			N_("start walk at all refs")),
 		OPT_BOOL(0, "stdin-packs", &opts.stdin_packs,
 			N_("scan pack-indexes listed by stdin for commits")),
 		OPT_BOOL(0, "stdin-commits", &opts.stdin_commits,
@@ -140,11 +143,16 @@ static int graph_write(int argc, const char **argv)
 			     builtin_commit_graph_write_options,
 			     builtin_commit_graph_write_usage, 0);
 
-	if (opts.stdin_packs && opts.stdin_commits)
-		die(_("cannot use both --stdin-commits and --stdin-packs"));
+	if (opts.reachable + opts.stdin_packs + opts.stdin_commits > 1)
+		die(_("use at most one of --reachable, --stdin-commits, or --stdin-packs"));
 	if (!opts.obj_dir)
 		opts.obj_dir = get_object_directory();
 
+	if (opts.reachable) {
+		write_commit_graph_reachable(opts.obj_dir, opts.append);
+		return 0;
+	}
+
 	string_list_init(&lines, 0);
 	if (opts.stdin_packs || opts.stdin_commits) {
 		struct strbuf buf = STRBUF_INIT;
diff --git a/commit-graph.c b/commit-graph.c
index 5b7fa707a5..212232e752 100644
--- a/commit-graph.c
+++ b/commit-graph.c
@@ -7,6 +7,7 @@
 #include "packfile.h"
 #include "commit.h"
 #include "object.h"
+#include "refs.h"
 #include "revision.h"
 #include "sha1-lookup.h"
 #include "commit-graph.h"
@@ -656,6 +657,25 @@ static void compute_generation_numbers(struct packed_commit_list* commits)
 	}
 }
 
+static int add_ref_to_list(const char *refname,
+			   const struct object_id *oid,
+			   int flags, void *cb_data)
+{
+	struct string_list *list = (struct string_list *)cb_data;
+
+	string_list_append(list, oid_to_hex(oid));
+	return 0;
+}
+
+void write_commit_graph_reachable(const char *obj_dir, int append)
+{
+	struct string_list list;
+
+	string_list_init(&list, 1);
+	for_each_ref(add_ref_to_list, &list);
+	write_commit_graph(obj_dir, NULL, &list, append);
+}
+
 void write_commit_graph(const char *obj_dir,
 			struct string_list *pack_indexes,
 			struct string_list *commit_hex,
diff --git a/commit-graph.h b/commit-graph.h
index a79b854470..506cb45fb1 100644
--- a/commit-graph.h
+++ b/commit-graph.h
@@ -48,6 +48,7 @@ struct commit_graph {
 
 struct commit_graph *load_commit_graph_one(const char *graph_file);
 
+void write_commit_graph_reachable(const char *obj_dir, int append);
 void write_commit_graph(const char *obj_dir,
 			struct string_list *pack_indexes,
 			struct string_list *commit_hex,
diff --git a/t/t5318-commit-graph.sh b/t/t5318-commit-graph.sh
index a9e8c774d5..2208c266b5 100755
--- a/t/t5318-commit-graph.sh
+++ b/t/t5318-commit-graph.sh
@@ -205,6 +205,16 @@ test_expect_success 'build graph from commits with append' '
 graph_git_behavior 'append graph, commit 8 vs merge 1' full commits/8 merge/1
 graph_git_behavior 'append graph, commit 8 vs merge 2' full commits/8 merge/2
 
+test_expect_success 'build graph using --reachable' '
+	cd "$TRASH_DIRECTORY/full" &&
+	git commit-graph write --reachable &&
+	test_path_is_file $objdir/info/commit-graph &&
+	graph_read_expect "11" "large_edges"
+'
+
+graph_git_behavior 'append graph, commit 8 vs merge 1' full commits/8 merge/1
+graph_git_behavior 'append graph, commit 8 vs merge 2' full commits/8 merge/2
+
 test_expect_success 'setup bare repo' '
 	cd "$TRASH_DIRECTORY" &&
 	git clone --bare --no-local full bare &&