php_excel

Native C extension for reading and writing Excel files in PHP, powered by LibXL. 7-10× faster than PhpSpreadsheet with substantially lower memory pressure. Full XLS and XLSX support: rich text, conditional formatting, formulas, autofilters, form controls, embedded charts, and structured tables. PHP 8.1+ minimum. 2.0 ground-up modernization shipped April 2026.

🚀 Install

Via PIE (PHP Foundation's PECL successor):

pie install iliaal/php-excel \
  --with-libxl-incdir=/path/to/libxl/include_c \
  --with-libxl-libdir=/path/to/libxl/lib64

Or build from source:

phpize
./configure --with-excel \
  --with-libxl-incdir=/path/to/libxl/include_c \
  --with-libxl-libdir=/path/to/libxl/lib64
make
sudo make install

Then add extension=excel.so to your php.ini.

LibXL is a commercial library; download it from libxl.com and point the configure flags at its include_c and lib64 directories.

🛠️ Getting started

<?php
$book = new ExcelBook(null, null, true); // xlsx mode
$book->setLocale('UTF-8');

$sheet = $book->addSheet('Sheet1');

$data = [
    [1, 1500, 'John', 'Doe'],
    [2,  750, 'Jane', 'Doe'],
];

$row = 1;
foreach ($data as $item) {
    $sheet->writeRow($row++, $item);
}

// formula
$sheet->write($row, 1, '=SUM(B1:B3)');

// untrusted input: AS_TEXT stores the string verbatim, with no '=' formula
// promotion. It takes a string, so cast first. See SECURITY.md.
$sheet->write($row, 2, (string) $userSuppliedValue, null, ExcelFormat::AS_TEXT);

// date with format
$dateFormat = new ExcelFormat($book);
$dateFormat->numberFormat(ExcelFormat::NUMFORMAT_DATE);
$sheet2 = $book->addSheet('Sheet2');
$sheet2->write(1, 0, (new DateTime('2024-08-02'))->getTimestamp(), $dateFormat, ExcelFormat::AS_DATE);

$book->save('output.xlsx');

save() stages the workbook to a temporary sibling file and renames it into place, so a failed save leaves the destination untouched. If the rename fails, local-path saves fail closed (return false); stream wrappers that omit rename() fall back to a direct write with a warning. Failed handle creation and rejected header, footer, font-size, and staging inputs emit warnings naming the cause. Suppress them with @ only where you handle false explicitly.

📊 Performance

Write 100,000 rows × 20 columns vs PhpSpreadsheet 5.5.0 on PHP 8.4.19 NTS, Apple M3:

Rows	Cells	php_excel	PhpSpreadsheet	Speedup
1,000	20K	0.05s / 85 MB	0.45s / 162 MB	10×
10,000	200K	0.55s / 153 MB	4.59s / 282 MB	9×
50,000	1M	2.72s / 508 MB	24.7s / 790 MB	9×
100,000	2M	5.37s / 908 MB	51.1s / 1,415 MB	10×

Reads are 8-9× faster than PhpSpreadsheet and 3× faster than OpenSpout, at the cost of memory that grows with the file, where OpenSpout streams in a flat 130 MB.

For read-heavy import paths, prefer readRow(), readCol(), or readRange() over per-cell read() loops. Pass false for $read_formula when cached values are enough, to skip the per-cell formula-text probe. For sparse sheets, readSparseRow() and readSparseCol() return only occupied cells keyed by their original column or row indexes.

Bulk-read bounds and indexes

Cell coordinates are zero-based. lastRow() and lastCol() return the exclusive end of the used range, while bulk readers take inclusive end coordinates. Subtract one when passing a used-range end to readRange(); readRow() and readCol() do this automatically for their default end of -1. Check that a range is nonempty before subtracting and reading it. The used range can extend beyond nonempty values, for example because of formatting.

Dense readers return packed arrays keyed from zero, even when the requested range starts elsewhere. Sparse readers keep the original sheet indexes and omit empty cells, but retain values such as numeric zero and boolean false.

$sheet = $book->addSheet('Read example');
$sheet->write(1, 1, 'A');
$sheet->write(1, 3, false);
$sheet->write(3, 1, 0);

$sheet->readRow(1, 1, 3);       // [0 => 'A', 1 => '', 2 => false]
$sheet->readSparseRow(1, 1, 3); // [1 => 'A', 3 => false]

// Read the data from row/column 1 through the last used cell.
$rowEnd = $sheet->lastRow();
$colEnd = $sheet->lastCol();
$rows = ($rowEnd > 1 && $colEnd > 1)
    ? $sheet->readRange(1, $rowEnd - 1, 1, $colEnd - 1)
    : [];
// $rows[0][0] corresponds to sheet cell (1, 1).

Bulk-write array keys

writeRow() and writeCol() consume values in PHP array iteration order and write consecutive cells starting at $start_column or $start_row. Array keys are ignored: neither numeric gaps nor associative keys select cell coordinates, and values are not sorted by key.

In particular, passing a readSparseRow() or readSparseCol() result directly to a bulk writer compacts its positions. To preserve sparse coordinates, write each returned value using its key (and an explicit offset if needed):

$source = $book->addSheet('Source');
$target = $book->addSheet('Copy');
$source->write(1, 1, 'A');
$source->write(1, 3, false);

$values = $source->readSparseRow(1, 1, 3); // [1 => 'A', 3 => false]
$target->writeRow(1, $values, 1);          // writes to columns 1 and 2
foreach ($values as $column => $value) {
    $target->write(2, $column, $value);    // preserves columns 1 and 3
}

For a sparse column, iterate readSparseCol() as $row => $value and call write($row, $targetColumn, $value). This copies returned values only; it does not copy formatting or clear cells omitted by the sparse reader. If empty positions should also be written, use a dense reader and pass the matching start coordinate to the bulk writer instead, subject to excel.skip_empty.

Formula text versus cached results

read(), readRow(), readCol(), readRange(), readSparseRow(), and readSparseCol() return formula text for formula cells by default, without its leading =. Pass false for $read_formula to read the stored cached result instead. This does not evaluate the formula: LibXL has no calculation engine.

Cached results may be stale or absent, especially after writing a formula or changing its inputs. Saving and reloading through php_excel does not refresh them. If you need current calculated results, recalculate and save the workbook in Excel or another compatible calculation engine before importing it.

$sheet->write(1, 1, 7);          // B2
$sheet->write(1, 2, '=B2*2');    // C2
$sheet->readRow(1, 2, 2);        // ['B2*2']
$sheet->readRow(1, 2, 2, false); // [0.0], not the calculated value 14

The zero above is the initial cached value for this newly written numeric formula, not a general signal that a formula is missing or invalid. Existing files can contain other cached values; php_excel does not check their freshness.

Native memory and PHP's memory_limit

PHP's memory_get_peak_usage() reports about 2 MB for php_excel in the benchmark above because LibXL allocates on the C heap, outside PHP's memory manager and memory_limit. PHP's memory counters do not include these native allocations, even with real_usage set to true. This allows php_excel to write 100,000 rows without raising PHP's 128 MB limit, but the same run still peaked at 908 MB of process virtual memory (VmPeak). save() without a path, to a stream-wrapper URL, or while open_basedir is set copies the entire workbook into a PHP string, so that copy also counts against memory_limit.

php_excel can still run out of memory or hit an operating-system or container memory limit. Size your workers and concurrency using process-level memory measurements (such as resident set size), not PHP's memory counters alone. PHP arrays, strings, and buffered stream input also consume PHP-managed memory and remain subject to memory_limit; see stream-loading limits.

📦 Classes

Class	Description
ExcelBook	Workbook management: create, load, save, sheets, fonts, formats, pictures
ExcelSheet	Cell read/write, formatting, printing, protection, hyperlinks, data validation
ExcelFormat	Cell formatting: colors, borders, number formats, alignment, patterns
ExcelFont	Font properties: name, size, bold, italic, underline, color
ExcelAutoFilter	AutoFilter operations and sorting
ExcelFilterColumn	Filter column criteria
ExcelRichString	Mixed-font text in a single cell
ExcelFormControl	Form controls: checkboxes, dropdowns, spinners, buttons
ExcelConditionalFormat	Conditional formatting style rules
ExcelConditionalFormatting	Conditional formatting ranges and rule application
ExcelCoreProperties	Workbook metadata: title, author, dates, categories
ExcelTable	Structured table support (xlsx)

2.0 added six new classes (ExcelRichString, ExcelFormControl, ExcelConditionalFormat, ExcelConditionalFormatting, ExcelCoreProperties, ExcelTable) plus full arginfo coverage: 399 typed parameters and 277 typed return values across the surface.

php.ini settings

Store LibXL credentials in php.ini instead of source code. The extension reads them automatically when you pass null to the constructor.

[excel]
excel.license_name="YOUR_LICENSE_NAME"
excel.license_key="YOUR_LICENSE_KEY"
excel.skip_empty=0

Skipping empty writes

excel.skip_empty controls write(), writeRow(), and writeCol():

• 0 (default): write null as a blank cell and write empty strings.
• 1: skip null; still write empty strings.
• 2: skip both null and empty strings, unless the write passes ExcelFormat::AS_TEXT.

A skipped write returns success but leaves the existing cell value and format unchanged. It does not clear the cell. Bulk writes still advance to the next coordinate, so skipped values leave gaps rather than shifting later values. Numeric zero, boolean false, and the string '0' are never skipped.

$sheet->writeRow(1, ['keep', 'replace', 'old'], 1);
$previous = ini_set('excel.skip_empty', '2');
$sheet->writeRow(1, [null, '', 0], 1);
$sheet->readRow(1, 1, 3); // ['keep', 'replace', 0.0]
ini_set('excel.skip_empty', $previous);

The setting is request-wide, not per workbook, and can be changed with ini_set(). Restore the previous value after a temporary override. To clear an existing cell with null, use mode 0. An explicit ExcelFormat::AS_TEXT writes an empty string even in mode 2. A blank formula, meaning an empty or whitespace-only body after an optional leading = (such as '' with ExcelFormat::AS_FORMULA, or '='), is written as an empty string, so mode 2 skips it. ExcelFormat::AS_NUMERIC_STRING empty strings are skipped like the default type. A lone ' is unescaped to an empty string and always written. null follows excel.skip_empty regardless of the data type.

🔗 Native PHP extensions

Companion native PHP extensions:

• mdparser: native CommonMark + GFM markdown parser via md4c. 15-30× faster than pure-PHP libraries.
• php_clickhouse: native ClickHouse client speaking the wire protocol directly. Picks up where SeasClick left off.
• pdo_duckdb: PDO driver for DuckDB, analytical SQL in your PHP stack.
• fastjson: drop-in faster ext/json, backed by yyjson. 6× encode, 2.7× decode, 5× validate.
• phpser: decoder-optimized binary serializer for cache workloads. Faster than igbinary on packed numerics and DTO batches.
• fast_uuid: high-throughput UUID generation (v1/v4/v7), batched CSPRNG and SIMD hex formatter, ramsey-compatible API.
• fastchart: native chart-rendering extension. 38 chart types behind one fluent OO API, SVG-canonical with PNG/JPG/WebP and optional PDF output.
• statgrab: system statistics (CPU, memory, disk, network) via libstatgrab, no parsing /proc by hand.
• phonetic: native phonetic name matching (Double Metaphone, Beider-Morse, Daitch-Mokotoff, NYSIIS, Match Rating), the encoders PHP core lacks.

📚 Read more

The launch post covers background, design rationale, and benchmark methodology: php_excel 2.0: The C Extension for Excel That PHP Should Have Had All Along.

API reference lives in docs/; usage examples live in tests/.

License

PHP License 3.01. See LICENSE.

LibXL itself is commercial. See libxl.com for licensing.

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