diff --git a/contrib/pageinspect/Makefile b/contrib/pageinspect/Makefile
index 4b6df96..d9d8177 100644
--- a/contrib/pageinspect/Makefile
+++ b/contrib/pageinspect/Makefile
@@ -19,7 +19,7 @@ DATA =  pageinspect--1.7--1.8.sql pageinspect--1.6--1.7.sql \
 	pageinspect--1.0--1.1.sql
 PGFILEDESC = "pageinspect - functions to inspect contents of database pages"
 
-REGRESS = page btree brin gin hash
+REGRESS = page btree brin gin hash checksum
 
 ifdef USE_PGXS
 PG_CONFIG = pg_config
diff --git a/contrib/pageinspect/expected/checksum.out b/contrib/pageinspect/expected/checksum.out
new file mode 100644
index 0000000..ae67f6c
--- /dev/null
+++ b/contrib/pageinspect/expected/checksum.out
@@ -0,0 +1,39 @@
+--
+-- Verify correct calculation of checksums
+--
+-- Postgres' checksum algorithm produces different answers on little-endian
+-- and big-endian machines.  The results of this test also vary depending
+-- on the configured block size.  This test has several different expected
+-- results files to handle the following possibilities:
+--
+--	BLCKSZ	end	file
+--	8K	LE	checksum.out
+--	8K	BE	checksum_1.out
+--	16K	LE	checksum_2.out
+--	16K	BE	checksum_3.out
+--	32K	LE	checksum_4.out
+--	32K	BE	checksum_5.out
+-- This is to label the results files with blocksize:
+SHOW block_size;
+ block_size 
+------------
+ 8192
+(1 row)
+
+SHOW block_size \gset
+-- Apply page_checksum() to some different data patterns and block numbers
+SELECT blkno,
+    page_checksum(decode(repeat('01', :block_size), 'hex'), blkno) AS checksum_01,
+    page_checksum(decode(repeat('04', :block_size), 'hex'), blkno) AS checksum_04,
+    page_checksum(decode(repeat('ff', :block_size), 'hex'), blkno) AS checksum_ff,
+    page_checksum(decode(repeat('abcd', :block_size / 2), 'hex'), blkno) AS checksum_abcd,
+    page_checksum(decode(repeat('e6d6', :block_size / 2), 'hex'), blkno) AS checksum_e6d6,
+    page_checksum(decode(repeat('4a5e', :block_size / 2), 'hex'), blkno) AS checksum_4a5e
+  FROM generate_series(0, 100, 50) AS a (blkno);
+ blkno | checksum_01 | checksum_04 | checksum_ff | checksum_abcd | checksum_e6d6 | checksum_4a5e 
+-------+-------------+-------------+-------------+---------------+---------------+---------------
+     0 |        1175 |       28338 |        3612 |        -30781 |        -16269 |        -27377
+    50 |        1225 |       28352 |        3598 |        -30795 |        -16251 |        -27391
+   100 |        1139 |       28438 |        3648 |        -30881 |        -16305 |        -27349
+(3 rows)
+
diff --git a/contrib/pageinspect/expected/checksum_1.out b/contrib/pageinspect/expected/checksum_1.out
new file mode 100644
index 0000000..942a302
--- /dev/null
+++ b/contrib/pageinspect/expected/checksum_1.out
@@ -0,0 +1,39 @@
+--
+-- Verify correct calculation of checksums
+--
+-- Postgres' checksum algorithm produces different answers on little-endian
+-- and big-endian machines.  The results of this test also vary depending
+-- on the configured block size.  This test has several different expected
+-- results files to handle the following possibilities:
+--
+--	BLCKSZ	end	file
+--	8K	LE	checksum.out
+--	8K	BE	checksum_1.out
+--	16K	LE	checksum_2.out
+--	16K	BE	checksum_3.out
+--	32K	LE	checksum_4.out
+--	32K	BE	checksum_5.out
+-- This is to label the results files with blocksize:
+SHOW block_size;
+ block_size 
+------------
+ 8192
+(1 row)
+
+SHOW block_size \gset
+-- Apply page_checksum() to some different data patterns and block numbers
+SELECT blkno,
+    page_checksum(decode(repeat('01', :block_size), 'hex'), blkno) AS checksum_01,
+    page_checksum(decode(repeat('04', :block_size), 'hex'), blkno) AS checksum_04,
+    page_checksum(decode(repeat('ff', :block_size), 'hex'), blkno) AS checksum_ff,
+    page_checksum(decode(repeat('abcd', :block_size / 2), 'hex'), blkno) AS checksum_abcd,
+    page_checksum(decode(repeat('e6d6', :block_size / 2), 'hex'), blkno) AS checksum_e6d6,
+    page_checksum(decode(repeat('4a5e', :block_size / 2), 'hex'), blkno) AS checksum_4a5e
+  FROM generate_series(0, 100, 50) AS a (blkno);
+ blkno | checksum_01 | checksum_04 | checksum_ff | checksum_abcd | checksum_e6d6 | checksum_4a5e 
+-------+-------------+-------------+-------------+---------------+---------------+---------------
+     0 |      -16327 |        8766 |       -2722 |         13757 |        -11485 |        -31426
+    50 |      -16281 |        8780 |       -2708 |         13771 |        -11503 |        -31440
+   100 |      -16235 |        8866 |       -2758 |         13721 |        -11577 |        -31518
+(3 rows)
+
diff --git a/contrib/pageinspect/expected/checksum_2.out b/contrib/pageinspect/expected/checksum_2.out
new file mode 100644
index 0000000..1c98f8f
--- /dev/null
+++ b/contrib/pageinspect/expected/checksum_2.out
@@ -0,0 +1,39 @@
+--
+-- Verify correct calculation of checksums
+--
+-- Postgres' checksum algorithm produces different answers on little-endian
+-- and big-endian machines.  The results of this test also vary depending
+-- on the configured block size.  This test has several different expected
+-- results files to handle the following possibilities:
+--
+--	BLCKSZ	end	file
+--	8K	LE	checksum.out
+--	8K	BE	checksum_1.out
+--	16K	LE	checksum_2.out
+--	16K	BE	checksum_3.out
+--	32K	LE	checksum_4.out
+--	32K	BE	checksum_5.out
+-- This is to label the results files with blocksize:
+SHOW block_size;
+ block_size 
+------------
+ 16384
+(1 row)
+
+SHOW block_size \gset
+-- Apply page_checksum() to some different data patterns and block numbers
+SELECT blkno,
+    page_checksum(decode(repeat('01', :block_size), 'hex'), blkno) AS checksum_01,
+    page_checksum(decode(repeat('04', :block_size), 'hex'), blkno) AS checksum_04,
+    page_checksum(decode(repeat('ff', :block_size), 'hex'), blkno) AS checksum_ff,
+    page_checksum(decode(repeat('abcd', :block_size / 2), 'hex'), blkno) AS checksum_abcd,
+    page_checksum(decode(repeat('e6d6', :block_size / 2), 'hex'), blkno) AS checksum_e6d6,
+    page_checksum(decode(repeat('4a5e', :block_size / 2), 'hex'), blkno) AS checksum_4a5e
+  FROM generate_series(0, 100, 50) AS a (blkno);
+ blkno | checksum_01 | checksum_04 | checksum_ff | checksum_abcd | checksum_e6d6 | checksum_4a5e 
+-------+-------------+-------------+-------------+---------------+---------------+---------------
+     0 |       11110 |       11537 |        5518 |         29279 |         -5920 |         24342
+    50 |       11064 |       11587 |        5472 |         29293 |         -5966 |         24388
+   100 |       11138 |       11509 |        5418 |         29371 |         -6012 |         24434
+(3 rows)
+
diff --git a/contrib/pageinspect/expected/checksum_3.out b/contrib/pageinspect/expected/checksum_3.out
new file mode 100644
index 0000000..7f62d22
--- /dev/null
+++ b/contrib/pageinspect/expected/checksum_3.out
@@ -0,0 +1,39 @@
+--
+-- Verify correct calculation of checksums
+--
+-- Postgres' checksum algorithm produces different answers on little-endian
+-- and big-endian machines.  The results of this test also vary depending
+-- on the configured block size.  This test has several different expected
+-- results files to handle the following possibilities:
+--
+--	BLCKSZ	end	file
+--	8K	LE	checksum.out
+--	8K	BE	checksum_1.out
+--	16K	LE	checksum_2.out
+--	16K	BE	checksum_3.out
+--	32K	LE	checksum_4.out
+--	32K	BE	checksum_5.out
+-- This is to label the results files with blocksize:
+SHOW block_size;
+ block_size 
+------------
+ 16384
+(1 row)
+
+SHOW block_size \gset
+-- Apply page_checksum() to some different data patterns and block numbers
+SELECT blkno,
+    page_checksum(decode(repeat('01', :block_size), 'hex'), blkno) AS checksum_01,
+    page_checksum(decode(repeat('04', :block_size), 'hex'), blkno) AS checksum_04,
+    page_checksum(decode(repeat('ff', :block_size), 'hex'), blkno) AS checksum_ff,
+    page_checksum(decode(repeat('abcd', :block_size / 2), 'hex'), blkno) AS checksum_abcd,
+    page_checksum(decode(repeat('e6d6', :block_size / 2), 'hex'), blkno) AS checksum_e6d6,
+    page_checksum(decode(repeat('4a5e', :block_size / 2), 'hex'), blkno) AS checksum_4a5e
+  FROM generate_series(0, 100, 50) AS a (blkno);
+ blkno | checksum_01 | checksum_04 | checksum_ff | checksum_abcd | checksum_e6d6 | checksum_4a5e 
+-------+-------------+-------------+-------------+---------------+---------------+---------------
+     0 |      -16158 |        9656 |      -23891 |          8765 |          8089 |          -626
+    50 |      -16172 |        9706 |      -23909 |          8815 |          8075 |          -672
+   100 |      -16250 |        9620 |      -23863 |          8737 |          8125 |          -718
+(3 rows)
+
diff --git a/contrib/pageinspect/expected/checksum_4.out b/contrib/pageinspect/expected/checksum_4.out
new file mode 100644
index 0000000..75d5ab8
--- /dev/null
+++ b/contrib/pageinspect/expected/checksum_4.out
@@ -0,0 +1,39 @@
+--
+-- Verify correct calculation of checksums
+--
+-- Postgres' checksum algorithm produces different answers on little-endian
+-- and big-endian machines.  The results of this test also vary depending
+-- on the configured block size.  This test has several different expected
+-- results files to handle the following possibilities:
+--
+--	BLCKSZ	end	file
+--	8K	LE	checksum.out
+--	8K	BE	checksum_1.out
+--	16K	LE	checksum_2.out
+--	16K	BE	checksum_3.out
+--	32K	LE	checksum_4.out
+--	32K	BE	checksum_5.out
+-- This is to label the results files with blocksize:
+SHOW block_size;
+ block_size 
+------------
+ 32768
+(1 row)
+
+SHOW block_size \gset
+-- Apply page_checksum() to some different data patterns and block numbers
+SELECT blkno,
+    page_checksum(decode(repeat('01', :block_size), 'hex'), blkno) AS checksum_01,
+    page_checksum(decode(repeat('04', :block_size), 'hex'), blkno) AS checksum_04,
+    page_checksum(decode(repeat('ff', :block_size), 'hex'), blkno) AS checksum_ff,
+    page_checksum(decode(repeat('abcd', :block_size / 2), 'hex'), blkno) AS checksum_abcd,
+    page_checksum(decode(repeat('e6d6', :block_size / 2), 'hex'), blkno) AS checksum_e6d6,
+    page_checksum(decode(repeat('4a5e', :block_size / 2), 'hex'), blkno) AS checksum_4a5e
+  FROM generate_series(0, 100, 50) AS a (blkno);
+ blkno | checksum_01 | checksum_04 | checksum_ff | checksum_abcd | checksum_e6d6 | checksum_4a5e 
+-------+-------------+-------------+-------------+---------------+---------------+---------------
+     0 |       26028 |       17735 |       21350 |         -8851 |        -17998 |         -7046
+    50 |       26042 |       17721 |       21400 |         -8837 |        -18012 |         -6996
+   100 |       26120 |       17771 |       21442 |         -8759 |        -18090 |         -6946
+(3 rows)
+
diff --git a/contrib/pageinspect/expected/checksum_5.out b/contrib/pageinspect/expected/checksum_5.out
new file mode 100644
index 0000000..3a68ccc
--- /dev/null
+++ b/contrib/pageinspect/expected/checksum_5.out
@@ -0,0 +1,39 @@
+--
+-- Verify correct calculation of checksums
+--
+-- Postgres' checksum algorithm produces different answers on little-endian
+-- and big-endian machines.  The results of this test also vary depending
+-- on the configured block size.  This test has several different expected
+-- results files to handle the following possibilities:
+--
+--	BLCKSZ	end	file
+--	8K	LE	checksum.out
+--	8K	BE	checksum_1.out
+--	16K	LE	checksum_2.out
+--	16K	BE	checksum_3.out
+--	32K	LE	checksum_4.out
+--	32K	BE	checksum_5.out
+-- This is to label the results files with blocksize:
+SHOW block_size;
+ block_size 
+------------
+ 32768
+(1 row)
+
+SHOW block_size \gset
+-- Apply page_checksum() to some different data patterns and block numbers
+SELECT blkno,
+    page_checksum(decode(repeat('01', :block_size), 'hex'), blkno) AS checksum_01,
+    page_checksum(decode(repeat('04', :block_size), 'hex'), blkno) AS checksum_04,
+    page_checksum(decode(repeat('ff', :block_size), 'hex'), blkno) AS checksum_ff,
+    page_checksum(decode(repeat('abcd', :block_size / 2), 'hex'), blkno) AS checksum_abcd,
+    page_checksum(decode(repeat('e6d6', :block_size / 2), 'hex'), blkno) AS checksum_e6d6,
+    page_checksum(decode(repeat('4a5e', :block_size / 2), 'hex'), blkno) AS checksum_4a5e
+  FROM generate_series(0, 100, 50) AS a (blkno);
+ blkno | checksum_01 | checksum_04 | checksum_ff | checksum_abcd | checksum_e6d6 | checksum_4a5e 
+-------+-------------+-------------+-------------+---------------+---------------+---------------
+     0 |      -14560 |      -27746 |       32614 |          2147 |         -8732 |        -27565
+    50 |      -14546 |      -27700 |       32632 |          2193 |         -8746 |        -27551
+   100 |      -14596 |      -27782 |       32578 |          2119 |         -8704 |        -27473
+(3 rows)
+
diff --git a/contrib/pageinspect/sql/checksum.sql b/contrib/pageinspect/sql/checksum.sql
new file mode 100644
index 0000000..fdb3250
--- /dev/null
+++ b/contrib/pageinspect/sql/checksum.sql
@@ -0,0 +1,30 @@
+--
+-- Verify correct calculation of checksums
+--
+-- Postgres' checksum algorithm produces different answers on little-endian
+-- and big-endian machines.  The results of this test also vary depending
+-- on the configured block size.  This test has several different expected
+-- results files to handle the following possibilities:
+--
+--	BLCKSZ	end	file
+--	8K	LE	checksum.out
+--	8K	BE	checksum_1.out
+--	16K	LE	checksum_2.out
+--	16K	BE	checksum_3.out
+--	32K	LE	checksum_4.out
+--	32K	BE	checksum_5.out
+
+-- This is to label the results files with blocksize:
+SHOW block_size;
+
+SHOW block_size \gset
+
+-- Apply page_checksum() to some different data patterns and block numbers
+SELECT blkno,
+    page_checksum(decode(repeat('01', :block_size), 'hex'), blkno) AS checksum_01,
+    page_checksum(decode(repeat('04', :block_size), 'hex'), blkno) AS checksum_04,
+    page_checksum(decode(repeat('ff', :block_size), 'hex'), blkno) AS checksum_ff,
+    page_checksum(decode(repeat('abcd', :block_size / 2), 'hex'), blkno) AS checksum_abcd,
+    page_checksum(decode(repeat('e6d6', :block_size / 2), 'hex'), blkno) AS checksum_e6d6,
+    page_checksum(decode(repeat('4a5e', :block_size / 2), 'hex'), blkno) AS checksum_4a5e
+  FROM generate_series(0, 100, 50) AS a (blkno);