diff --git a/common/cmd_ext4.c b/common/cmd_ext4.c
index 68b047b..6d75dd2 100644
--- a/common/cmd_ext4.c
+++ b/common/cmd_ext4.c
@@ -42,6 +42,12 @@
 #include <usb.h>
 #endif
 
+int do_ext4_size(cmd_tbl_t *cmdtp, int flag, int argc,
+						char *const argv[])
+{
+	return do_size(cmdtp, flag, argc, argv, FS_TYPE_EXT);
+}
+
 int do_ext4_load(cmd_tbl_t *cmdtp, int flag, int argc,
 						char *const argv[])
 {
@@ -113,6 +119,14 @@
 
 #endif
 
+U_BOOT_CMD(
+	ext4size,	4,	0,	do_ext4_size,
+	"determine a file's size",
+	"<interface> <dev[:part]> <filename>\n"
+	"    - Find file 'filename' from 'dev' on 'interface'\n"
+	"      and determine its size."
+);
+
 U_BOOT_CMD(ext4ls, 4, 1, do_ext4_ls,
 	   "list files in a directory (default /)",
 	   "<interface> <dev[:part]> [directory]\n"
diff --git a/common/cmd_fat.c b/common/cmd_fat.c
index a478017..633fbf1 100644
--- a/common/cmd_fat.c
+++ b/common/cmd_fat.c
@@ -18,6 +18,19 @@
 #include <fat.h>
 #include <fs.h>
 
+int do_fat_size(cmd_tbl_t *cmdtp, int flag, int argc, char * const argv[])
+{
+	return do_size(cmdtp, flag, argc, argv, FS_TYPE_FAT);
+}
+
+U_BOOT_CMD(
+	fatsize,	4,	0,	do_fat_size,
+	"determine a file's size",
+	"<interface> <dev[:part]> <filename>\n"
+	"    - Find file 'filename' from 'dev' on 'interface'\n"
+	"      and determine its size."
+);
+
 int do_fat_fsload (cmd_tbl_t *cmdtp, int flag, int argc, char * const argv[])
 {
 	return do_load(cmdtp, flag, argc, argv, FS_TYPE_FAT);
diff --git a/common/cmd_fs.c b/common/cmd_fs.c
index 78590d2..6754340 100644
--- a/common/cmd_fs.c
+++ b/common/cmd_fs.c
@@ -20,6 +20,19 @@
 #include <command.h>
 #include <fs.h>
 
+static int do_size_wrapper(cmd_tbl_t *cmdtp, int flag, int argc, char * const argv[])
+{
+	return do_size(cmdtp, flag, argc, argv, FS_TYPE_ANY);
+}
+
+U_BOOT_CMD(
+	size,	4,	0,	do_size_wrapper,
+	"determine a file's size",
+	"<interface> <dev[:part]> <filename>\n"
+	"    - Find file 'filename' from 'dev' on 'interface'\n"
+	"      and determine its size."
+);
+
 static int do_load_wrapper(cmd_tbl_t *cmdtp, int flag, int argc,
 				char * const argv[])
 {
diff --git a/fs/ext4/ext4fs.c b/fs/ext4/ext4fs.c
index 417ce7b..cbdc220 100644
--- a/fs/ext4/ext4fs.c
+++ b/fs/ext4/ext4fs.c
@@ -182,6 +182,11 @@
 	return file_len >= 0;
 }
 
+int ext4fs_size(const char *filename)
+{
+	return ext4fs_open(filename);
+}
+
 int ext4fs_read(char *buf, unsigned len)
 {
 	if (ext4fs_root == NULL || ext4fs_file == NULL)
diff --git a/fs/fat/fat.c b/fs/fat/fat.c
index 54f42ea..561921f 100644
--- a/fs/fat/fat.c
+++ b/fs/fat/fat.c
@@ -1243,6 +1243,11 @@
 	return sz >= 0;
 }
 
+int fat_size(const char *filename)
+{
+	return do_fat_read_at(filename, 0, NULL, 0, LS_NO, 1);
+}
+
 long file_fat_read_at(const char *filename, unsigned long pos, void *buffer,
 		      unsigned long maxsize)
 {
diff --git a/fs/fs.c b/fs/fs.c
index ea15c5f..dd680f3 100644
--- a/fs/fs.c
+++ b/fs/fs.c
@@ -46,6 +46,11 @@
 	return 0;
 }
 
+static inline int fs_size_unsupported(const char *filename)
+{
+	return -1;
+}
+
 static inline int fs_read_unsupported(const char *filename, void *buf,
 				      int offset, int len)
 {
@@ -77,6 +82,7 @@
 		     disk_partition_t *fs_partition);
 	int (*ls)(const char *dirname);
 	int (*exists)(const char *filename);
+	int (*size)(const char *filename);
 	int (*read)(const char *filename, void *buf, int offset, int len);
 	int (*write)(const char *filename, void *buf, int offset, int len);
 	void (*close)(void);
@@ -91,6 +97,7 @@
 		.close = fat_close,
 		.ls = file_fat_ls,
 		.exists = fat_exists,
+		.size = fat_size,
 		.read = fat_read_file,
 		.write = fs_write_unsupported,
 	},
@@ -103,6 +110,7 @@
 		.close = ext4fs_close,
 		.ls = ext4fs_ls,
 		.exists = ext4fs_exists,
+		.size = ext4fs_size,
 		.read = ext4_read_file,
 		.write = fs_write_unsupported,
 	},
@@ -115,6 +123,7 @@
 		.close = sandbox_fs_close,
 		.ls = sandbox_fs_ls,
 		.exists = sandbox_fs_exists,
+		.size = sandbox_fs_size,
 		.read = fs_read_sandbox,
 		.write = fs_write_sandbox,
 	},
@@ -126,6 +135,7 @@
 		.close = fs_close_unsupported,
 		.ls = fs_ls_unsupported,
 		.exists = fs_exists_unsupported,
+		.size = fs_size_unsupported,
 		.read = fs_read_unsupported,
 		.write = fs_write_unsupported,
 	},
@@ -223,6 +233,19 @@
 	return ret;
 }
 
+int fs_size(const char *filename)
+{
+	int ret;
+
+	struct fstype_info *info = fs_get_info(fs_type);
+
+	ret = info->size(filename);
+
+	fs_close();
+
+	return ret;
+}
+
 int fs_read(const char *filename, ulong addr, int offset, int len)
 {
 	struct fstype_info *info = fs_get_info(fs_type);
@@ -266,6 +289,26 @@
 	return ret;
 }
 
+int do_size(cmd_tbl_t *cmdtp, int flag, int argc, char * const argv[],
+		int fstype)
+{
+	int size;
+
+	if (argc != 4)
+		return CMD_RET_USAGE;
+
+	if (fs_set_blk_dev(argv[1], argv[2], fstype))
+		return 1;
+
+	size = fs_size(argv[3]);
+	if (size < 0)
+		return CMD_RET_FAILURE;
+
+	setenv_hex("filesize", size);
+
+	return 0;
+}
+
 int do_load(cmd_tbl_t *cmdtp, int flag, int argc, char * const argv[],
 		int fstype)
 {
diff --git a/fs/sandbox/sandboxfs.c b/fs/sandbox/sandboxfs.c
index 8507978..ba6402c 100644
--- a/fs/sandbox/sandboxfs.c
+++ b/fs/sandbox/sandboxfs.c
@@ -80,6 +80,11 @@
 	return sz >= 0;
 }
 
+int sandbox_fs_size(const char *filename)
+{
+	return os_get_filesize(filename);
+}
+
 void sandbox_fs_close(void)
 {
 }
diff --git a/include/ext4fs.h b/include/ext4fs.h
index fbbb002..6c419f3 100644
--- a/include/ext4fs.h
+++ b/include/ext4fs.h
@@ -136,6 +136,7 @@
 void ext4fs_reinit_global(void);
 int ext4fs_ls(const char *dirname);
 int ext4fs_exists(const char *filename);
+int ext4fs_size(const char *filename);
 void ext4fs_free_node(struct ext2fs_node *node, struct ext2fs_node *currroot);
 int ext4fs_devread(lbaint_t sector, int byte_offset, int byte_len, char *buf);
 void ext4fs_set_blk_dev(block_dev_desc_t *rbdd, disk_partition_t *info);
diff --git a/include/fat.h b/include/fat.h
index 63cf787..20ca3f3 100644
--- a/include/fat.h
+++ b/include/fat.h
@@ -198,6 +198,7 @@
 int file_fat_detectfs(void);
 int file_fat_ls(const char *dir);
 int fat_exists(const char *filename);
+int fat_size(const char *filename);
 long file_fat_read_at(const char *filename, unsigned long pos, void *buffer,
 		      unsigned long maxsize);
 long file_fat_read(const char *filename, void *buffer, unsigned long maxsize);
diff --git a/include/fs.h b/include/fs.h
index 26de053..06a45f2 100644
--- a/include/fs.h
+++ b/include/fs.h
@@ -51,6 +51,13 @@
 int fs_exists(const char *filename);
 
 /*
+ * Determine a file's size
+ *
+ * Returns the file's size in bytes, or a negative value if it doesn't exist.
+ */
+int fs_size(const char *filename);
+
+/*
  * Read file "filename" from the partition previously set by fs_set_blk_dev(),
  * to address "addr", starting at byte offset "offset", and reading "len"
  * bytes. "offset" may be 0 to read from the start of the file. "len" may be
@@ -75,6 +82,8 @@
  * Common implementation for various filesystem commands, optionally limited
  * to a specific filesystem type via the fstype parameter.
  */
+int do_size(cmd_tbl_t *cmdtp, int flag, int argc, char * const argv[],
+		int fstype);
 int do_load(cmd_tbl_t *cmdtp, int flag, int argc, char * const argv[],
 		int fstype);
 int do_ls(cmd_tbl_t *cmdtp, int flag, int argc, char * const argv[],
diff --git a/include/sandboxfs.h b/include/sandboxfs.h
index a51ad13..e7c3262 100644
--- a/include/sandboxfs.h
+++ b/include/sandboxfs.h
@@ -26,6 +26,7 @@
 void sandbox_fs_close(void);
 int sandbox_fs_ls(const char *dirname);
 int sandbox_fs_exists(const char *filename);
+int sandbox_fs_size(const char *filename);
 int fs_read_sandbox(const char *filename, void *buf, int offset, int len);
 int fs_write_sandbox(const char *filename, void *buf, int offset, int len);