Oracle has provided a Beautiful script to check the Header Information of Oracle Export Dumpfile.

Refer How to Gather the Header Information and the Content of an Export Dumpfile ? (Doc ID 462488.1) for More Info.

CREATE OR REPLACE PROCEDURE show_dumpfile_info(
  p_dir  VARCHAR2 DEFAULT 'DATA_PUMP_DIR',
  p_file VARCHAR2 DEFAULT 'EXPDAT.DMP')
AS
-- p_dir        = directory object where dump file can be found
-- p_file       = simple filename of export dump file (case-sensitive)
  v_separator   VARCHAR2(80) := '--------------------------------------' ||
                                '--------------------------------------';
  v_path        all_directories.directory_path%type := '?';
  v_filetype    NUMBER;                 -- 0=unknown 1=expdp 2=exp 3=ext
  v_fileversion VARCHAR2(15);           -- 0.1=10gR1 1.1=10gR2 (etc.)
  v_info_table  sys.ku$_dumpfile_info;  -- PL/SQL table with file info
  type valtype  IS VARRAY(23) OF VARCHAR2(2048);
  var_values    valtype := valtype();
  no_file_found EXCEPTION;
  PRAGMA        exception_init(no_file_found, -39211);

BEGIN

-- Dump file details:
-- ==================
-- For Oracle10g Release 2 and higher:
--    dbms_datapump.KU$_DFHDR_FILE_VERSION        CONSTANT NUMBER := 1;
--    dbms_datapump.KU$_DFHDR_MASTER_PRESENT      CONSTANT NUMBER := 2;
--    dbms_datapump.KU$_DFHDR_GUID                CONSTANT NUMBER := 3;
--    dbms_datapump.KU$_DFHDR_FILE_NUMBER         CONSTANT NUMBER := 4;
--    dbms_datapump.KU$_DFHDR_CHARSET_ID          CONSTANT NUMBER := 5;
--    dbms_datapump.KU$_DFHDR_CREATION_DATE       CONSTANT NUMBER := 6;
--    dbms_datapump.KU$_DFHDR_FLAGS               CONSTANT NUMBER := 7;
--    dbms_datapump.KU$_DFHDR_JOB_NAME            CONSTANT NUMBER := 8;
--    dbms_datapump.KU$_DFHDR_PLATFORM            CONSTANT NUMBER := 9;
--    dbms_datapump.KU$_DFHDR_INSTANCE            CONSTANT NUMBER := 10;
--    dbms_datapump.KU$_DFHDR_LANGUAGE            CONSTANT NUMBER := 11;
--    dbms_datapump.KU$_DFHDR_BLOCKSIZE           CONSTANT NUMBER := 12;
--    dbms_datapump.KU$_DFHDR_DIRPATH             CONSTANT NUMBER := 13;
--    dbms_datapump.KU$_DFHDR_METADATA_COMPRESSED CONSTANT NUMBER := 14;
--    dbms_datapump.KU$_DFHDR_DB_VERSION          CONSTANT NUMBER := 15;
-- For Oracle11gR1:
--    dbms_datapump.KU$_DFHDR_MASTER_PIECE_COUNT  CONSTANT NUMBER := 16;
--    dbms_datapump.KU$_DFHDR_MASTER_PIECE_NUMBER CONSTANT NUMBER := 17;
--    dbms_datapump.KU$_DFHDR_DATA_COMPRESSED     CONSTANT NUMBER := 18;
--    dbms_datapump.KU$_DFHDR_METADATA_ENCRYPTED  CONSTANT NUMBER := 19;
--    dbms_datapump.KU$_DFHDR_DATA_ENCRYPTED      CONSTANT NUMBER := 20;
-- For Oracle11gR2:
--    dbms_datapump.KU$_DFHDR_COLUMNS_ENCRYPTED   CONSTANT NUMBER := 21;
--    dbms_datapump.KU$_DFHDR_ENCRIPTION_MODE     CONSTANT NUMBER := 22;
-- For Oracle12cR1:
--    dbms_datapump.KU$_DFHDR_COMPRESSION_ALG     CONSTANT NUMBER := 23;

-- For Oracle10gR2: KU$_DFHDR_MAX_ITEM_CODE       CONSTANT NUMBER := 15;
-- For Oracle11gR1: KU$_DFHDR_MAX_ITEM_CODE       CONSTANT NUMBER := 20;
-- For Oracle11gR2: KU$_DFHDR_MAX_ITEM_CODE       CONSTANT NUMBER := 22;
-- For Oracle12cR1: KU$_DFHDR_MAX_ITEM_CODE       CONSTANT NUMBER := 23;

-- Show header output info:
-- ========================

  dbms_output.put_line(v_separator);
  dbms_output.put_line('Purpose..: Obtain details about export ' ||
        'dumpfile.        Version: 18-DEC-2013');
  dbms_output.put_line('Required.: RDBMS version: 10.2.0.1.0 or higher');
  dbms_output.put_line('.          ' ||
        'Export dumpfile version: 7.3.4.0.0 or higher');
  dbms_output.put_line('.          ' ||
        'Export Data Pump dumpfile version: 10.1.0.1.0 or higher');
  dbms_output.put_line('Usage....: ' ||
        'execute show_dumfile_info(''DIRECTORY'', ''DUMPFILE'');');
  dbms_output.put_line('Example..: ' ||
        'exec show_dumfile_info(''MY_DIR'', ''expdp_s.dmp'')');
  dbms_output.put_line(v_separator);
  dbms_output.put_line('Filename.: ' || p_file);
  dbms_output.put_line('Directory: ' || p_dir);

-- Retrieve Export dumpfile details:
-- =================================

  SELECT directory_path INTO v_path FROM all_directories
   WHERE directory_name = p_dir
      OR directory_name = UPPER(p_dir);

  dbms_datapump.get_dumpfile_info(
           filename   => p_file,       directory => UPPER(p_dir),
           info_table => v_info_table, filetype  => v_filetype);

  var_values.EXTEND(23);
  FOR i in 1 .. 23 LOOP
    BEGIN
      SELECT value INTO var_values(i) FROM TABLE(v_info_table)
       WHERE item_code = i;
    EXCEPTION WHEN OTHERS THEN var_values(i) := '';
    END;
  END LOOP;

  dbms_output.put_line('Disk Path: ' || v_path);

  IF v_filetype >= 1 THEN
    -- Get characterset name:
    BEGIN
      SELECT var_values(5) || ' (' || nls_charset_name(var_values(5)) ||
        ')' INTO var_values(5) FROM dual;
    EXCEPTION WHEN OTHERS THEN null;
    END;
    IF v_filetype = 2 THEN
      dbms_output.put_line(
         'Filetype.: ' || v_filetype || ' (Original Export dumpfile)');
      dbms_output.put_line(v_separator);
      SELECT DECODE(var_values(13), '0', '0 (Conventional Path)',
        '1', '1 (Direct Path)', var_values(13))
        INTO var_values(13) FROM dual;
      dbms_output.put_line('...Characterset ID of source db..: ' || var_values(5));
      dbms_output.put_line('...Direct Path Export Mode.......: ' || var_values(13));
      dbms_output.put_line('...Export Version................: ' || var_values(15));
    ELSIF v_filetype = 1 OR v_filetype = 3 THEN
      SELECT SUBSTR(var_values(1), 1, 15) INTO v_fileversion FROM dual;
      SELECT DECODE(var_values(1),
                    '0.1', '0.1 (Oracle10g Release 1: 10.1.0.x)',
                    '1.1', '1.1 (Oracle10g Release 2: 10.2.0.x)',
                    '2.1', '2.1 (Oracle11g Release 1: 11.1.0.x)',
                    '3.1', '3.1 (Oracle11g Release 2: 11.2.0.x)',
                    '4.1', '4.1 (Oracle12c Release 1: 12.1.0.x)',
        var_values(1)) INTO var_values(1) FROM dual;
      SELECT DECODE(var_values(2), '0', '0 (No)', '1', '1 (Yes)',
        var_values(2)) INTO var_values(2) FROM dual;
      SELECT DECODE(var_values(14), '0', '0 (No)', '1', '1 (Yes)',
        var_values(14)) INTO var_values(14) FROM dual;
      SELECT DECODE(var_values(18), '0', '0 (No)', '1', '1 (Yes)',
        var_values(18)) INTO var_values(18) FROM dual;
      SELECT DECODE(var_values(19), '0', '0 (No)', '1', '1 (Yes)',
        var_values(19)) INTO var_values(19) FROM dual;
      SELECT DECODE(var_values(20), '0', '0 (No)', '1', '1 (Yes)',
        var_values(20)) INTO var_values(20) FROM dual;
      SELECT DECODE(var_values(21), '0', '0 (No)', '1', '1 (Yes)',
        var_values(21)) INTO var_values(21) FROM dual;
      SELECT DECODE(var_values(22),
                    '1', '1 (Unknown)',
                    '2', '2 (None)',
                    '3', '3 (Password)',
                    '4', '4 (Password and Wallet)',
                    '5', '5 (Wallet)',
        var_values(22)) INTO var_values(22) FROM dual;
      SELECT DECODE(var_values(23),
                    '2', '2 (None)',
                    '3', '3 (Basic)',
                    '4', '4 (Low)',
                    '5', '5 (Medium)',
                    '6', '6 (High)',
        var_values(23)) INTO var_values(23) FROM dual;
      IF v_filetype = 1 THEN
        dbms_output.put_line(
           'Filetype.: ' || v_filetype || ' (Export Data Pump dumpfile)');
        dbms_output.put_line(v_separator);
        dbms_output.put_line('...Database Job Version..........: ' || var_values(15));
        dbms_output.put_line('...Internal Dump File Version....: ' || var_values(1));
        dbms_output.put_line('...Creation Date.................: ' || var_values(6));
        dbms_output.put_line('...File Number (in dump file set): ' || var_values(4));
        dbms_output.put_line('...Master Present in dump file...: ' || var_values(2));
        IF dbms_datapump.KU$_DFHDR_MAX_ITEM_CODE > 15 AND v_fileversion >= '2.1' THEN
          dbms_output.put_line('...Master in how many dump files.: ' || var_values(16));
          dbms_output.put_line('...Master Piece Number in file...: ' || var_values(17));
        END IF;
        dbms_output.put_line('...Operating System of source db.: ' || var_values(9));
        IF v_fileversion >= '2.1' THEN
          dbms_output.put_line('...Instance Name of source db....: ' || var_values(10));
        END IF;
        dbms_output.put_line('...Characterset ID of source db..: ' || var_values(5));
        dbms_output.put_line('...Language Name of characterset.: ' || var_values(11));
        dbms_output.put_line('...Job Name......................: ' || var_values(8));
        dbms_output.put_line('...GUID (unique job identifier)..: ' || var_values(3));
        dbms_output.put_line('...Block size dump file (bytes)..: ' || var_values(12));
        dbms_output.put_line('...Metadata Compressed...........: ' || var_values(14));
        IF dbms_datapump.KU$_DFHDR_MAX_ITEM_CODE > 15 THEN
          dbms_output.put_line('...Data Compressed...............: ' || var_values(18));
          IF dbms_datapump.KU$_DFHDR_MAX_ITEM_CODE > 22 AND v_fileversion >= '4.1' THEN
            dbms_output.put_line('...Compression Algorithm.........: ' || var_values(23));
          END IF;
          dbms_output.put_line('...Metadata Encrypted............: ' || var_values(19));
          dbms_output.put_line('...Table Data Encrypted..........: ' || var_values(20));
          dbms_output.put_line('...Column Data Encrypted.........: ' || var_values(21));
          dbms_output.put_line('...Encryption Mode...............: ' || var_values(22));
        END IF;
      ELSE
        dbms_output.put_line(
           'Filetype.: ' || v_filetype || ' (External Table dumpfile)');
        dbms_output.put_line(v_separator);
        dbms_output.put_line('...Database Job Version..........: ' || var_values(15));
        dbms_output.put_line('...Internal Dump File Version....: ' || var_values(1));
        dbms_output.put_line('...Creation Date.................: ' || var_values(6));
        dbms_output.put_line('...File Number (in dump file set): ' || var_values(4));
        dbms_output.put_line('...Operating System of source db.: ' || var_values(9));
        IF v_fileversion >= '2.1' THEN
          dbms_output.put_line('...Instance Name of source db....: ' || var_values(10));
        END IF;
        dbms_output.put_line('...Characterset ID of source db..: ' || var_values(5));
        dbms_output.put_line('...Language Name of characterset.: ' || var_values(11));
        dbms_output.put_line('...GUID (unique job identifier)..: ' || var_values(3));
        dbms_output.put_line('...Block size dump file (bytes)..: ' || var_values(12));
        IF dbms_datapump.KU$_DFHDR_MAX_ITEM_CODE > 15 THEN
          dbms_output.put_line('...Data Compressed...............: ' || var_values(18));
          IF dbms_datapump.KU$_DFHDR_MAX_ITEM_CODE > 22 AND v_fileversion >= '4.1' THEN
            dbms_output.put_line('...Compression Algorithm.........: ' || var_values(23));
          END IF;
          dbms_output.put_line('...Table Data Encrypted..........: ' || var_values(20));
          dbms_output.put_line('...Encryption Mode...............: ' || var_values(22));
        END IF;
      END IF;
      dbms_output.put_line('...Internal Flag Values..........: ' || var_values(7));
      dbms_output.put_line('...Max Items Code (Info Items)...: ' ||
                  dbms_datapump.KU$_DFHDR_MAX_ITEM_CODE);
    END IF;
  ELSE
    dbms_output.put_line('Filetype.: ' || v_filetype);
    dbms_output.put_line(v_separator);
    dbms_output.put_line('ERROR....: Not an export dumpfile.');
  END IF;
  dbms_output.put_line(v_separator);

EXCEPTION
  WHEN no_data_found THEN
    dbms_output.put_line('Disk Path: ?');
    dbms_output.put_line('Filetype.: ?');
    dbms_output.put_line(v_separator);
    dbms_output.put_line('ERROR....: Directory Object does not exist.');
    dbms_output.put_line(v_separator);
  WHEN no_file_found THEN
    dbms_output.put_line('Disk Path: ' || v_path);
    dbms_output.put_line('Filetype.: ?');
    dbms_output.put_line(v_separator);
    dbms_output.put_line('ERROR....: File does not exist.');
    dbms_output.put_line(v_separator);
END;
/

Lets Execute the Procedure and Observe the Output.

SQL> SET serveroutput on SIZE 1000000
SQL> exec show_dumpfile_info('DATA_PUMP_DIR', 'EXPDAT.DMP') ;
----------------------------------------------------------------------------
Purpose..: Obtain details about export dumpfile.        Version: 18-DEC-2013
Required.: RDBMS version: 10.2.0.1.0 or higher
.          Export dumpfile version: 7.3.4.0.0 or higher
.          Export Data Pump dumpfile version: 10.1.0.1.0 or higher
Usage....: execute show_dumfile_info('DIRECTORY', 'DUMPFILE');
Example..: exec show_dumfile_info('MY_DIR', 'expdp_s.dmp')
----------------------------------------------------------------------------
Filename.: EXPDAT.DMP
Directory: DATA_PUMP_DIR
Disk Path: C:\app\Dell\product\21c\admin\xe\dpdump/
Filetype.: 1 (Export Data Pump dumpfile)
----------------------------------------------------------------------------
...Database Job Version..........: 21.00.00.00.00
...Internal Dump File Version....: 5.1
...Creation Date.................: Mon Sep 12 13:14:38 2022
...File Number (in dump file set): 1
...Master Present in dump file...: 1 (Yes)
...Master in how many dump files.: 1
...Master Piece Number in file...: 1
...Operating System of source db.: <>
...Instance Name of source db....: DESKTOP-<>:xe
...Characterset ID of source db..: 873 (AL32UTF8)
...Language Name of characterset.: AL32UTF8
...Job Name......................: "SYS"."SYS_EXPORT_FULL_01"
...GUID (unique job identifier)..: <>
...Block size dump file (bytes)..: 4096
...Metadata Compressed...........: 1 (Yes)
...Data Compressed...............: 0 (No)
...Compression Algorithm.........: 3 (Basic)
...Metadata Encrypted............: 0 (No)
...Table Data Encrypted..........: 0 (No)
...Column Data Encrypted.........: 0 (No)
...Encryption Mode...............: 2 (None)
...Internal Flag Values..........: 514
...Max Items Code (Info Items)...: 26
----------------------------------------------------------------------------

PL/SQL procedure successfully completed.

SQL>