以下并非真正的扩展库，它们属于 PHP 内核的一部分，不能通过编译选项将其排除。
Arrays
Classes/Objects
Date/Time
Directories
Errors and Logging
Program Execution
Filesystem
Function handling
i18n
PHP Options/Info
Mail
Math
Misc.
Network
Output Control
POSIX Regex
Sessions
Streams
Strings
Tokenizer
Unicode
URLs
Variables
以下扩展库绑定在 PHP 发行包中。
Apache
BC math
Bzip2
Calendar
COM
ctype
CURL
dba
dBase
DOM
.NET
Exif
FrontBase
FDF
FTP
gettext
GMP
hash
Firebird/InterBase
iconv
Informix
Image
IMAP
JSON
LDAP
libxml
Multibyte String
mcrypt
mhash
Mimetype
Ming (flash)
mSQL
MS SQL Server
MySQL
mysqli
Ncurses
NSAPI
Object Aggregation
OCI8
OpenSSL
PCNTL
PCRE
PDO
MS SQL Server (PDO)
Firebird/Interbase (PDO)
MySQL (PDO)
Oracle (PDO)
ODBC and DB2 (PDO)
PostgreSQL (PDO)
SQLite (PDO)
PostgreSQL
POSIX
Pspell
Readline
Recode
Semaphore
shmop
SimpleXML
SNMP
SOAP
Sockets
spl
SQLite
SVN
Sybase
tidy
ODBC
WDDX
XML
XMLReader
XML-RPC
XSL
XSLT
Zip
Zlib
要编译以下扩展库，需要外部的库。
BBCode
ClibPDF
Crack
DB++
dbx
DOM XML
enchant
fam
Fileinfo
FriBiDi
GeoIP
haru
Hyperwave
Hyperwave API
ibm_db2
Imagick Image Library
Ingres II
IRC Gateway
Java
MaxDB
MCAL
Memcache
mnoGoSearch
Msession
muscat
Newt
OGG/Vorbis
openal
Oracle
OvrimosSQL
Paradox
PDF
IBM (PDO)
Informix (PDO)
Verisign Payflow Pro
PS
qtdom
radius
Rar
Session PgSQL
ssh2
SWF
swish
vpopmail
xattr
xdiff
YAZ
以下扩展来自 » PECL。还有更多的 PECL 扩展但在 PHP 手册中尚未有文档。
APC
APD
bcompiler
Classkit
Cybercash
CyberMUT
Cyrus IMAP
Direct IO
Expect
filePro
Filter
gnupg
HTTP
id3
IIS Functions
kadm5
LZF
Mailparse
MCVE
gopher
YP/NIS
Lotus Notes
Parsekit
phar
Printer
RPMReader
runkit
SAM
SCA
SDO
SDO DAS XML
SDO-DAS-Relational
Statistics
TCP Wrappers
W32api
win32ps
win32service
XMLWriter