H5CPP — High-Performance HDF5 for Modern C++

OS / Compiler	GCC 13	GCC 14	GCC 15	Clang 17	Clang 18	Clang 19	Clang 20	Apple Clang	MSVC
Ubuntu 22.04
Ubuntu 24.04
macOS 15
Windows

H5CPP is a modern C++ template library for serial and parallel HDF5 I/O. It provides type-safe RAII wrappers, high-level create / read / write / append operations, and seamless interoperability with the native HDF5 C API. Chunked and compressed datasets, extendable packet-table streams, hyperslab selection, custom datatypes, and MPI parallel I/O are all supported. HDF5 files written by H5CPP are readable from Python, R, MATLAB, Fortran, Julia, and any other HDF5-capable environment.

Quick Start

#include <h5cpp/all>
#include <vector>

int main() {
    auto fd = h5::create("example.h5", H5F_ACC_TRUNC);

    std::vector<float> data = {1.f, 2.f, 3.f, 4.f, 5.f};
    h5::write(fd, "sensor/readings", data);

    auto result = h5::read<std::vector<float>>(fd, "sensor/readings");
    // result == {1.f, 2.f, 3.f, 4.f, 5.f}
}

find_package(HDF5 REQUIRED)
find_package(h5cpp REQUIRED)
target_link_libraries(my_app PRIVATE h5cpp::h5cpp)

Requirements

Requirement	Minimum	Tested ceiling
C++ standard	C++17	C++23
HDF5	1.10.x	1.12.2
CMake	3.22	—

C++20 upgrades the I/O pipeline to lock-free queues and enables h5::view<T> streaming ranges. C++23 adds std::float16_t dataset support.

Installation

From GitHub Releases — pre-built packages for each tagged release:

Platform	Package
Ubuntu / Debian (amd64, arm64)	.deb via Releases
RHEL / Fedora (x86_64, aarch64)	.rpm via Releases
macOS 15 arm64	.pkg via Releases
Windows x64	NSIS .exe via Releases

From source:

git clone https://github.com/vargalabs/h5cpp.git
cmake -B build -DCMAKE_BUILD_TYPE=Release -DH5CPP_BUILD_TESTS=OFF
cmake --install build

Supported Types

Category	Types
Numeric	bool, int8_t–int64_t, uint8_t–uint64_t, float, double, long double, std::complex<T>, std::float16_t (C++23)
Strings	std::string, char[], variable-length HDF5 strings
STL sequences	std::vector, std::valarray, std::array, std::deque
STL node-based	std::list, std::forward_list, std::set, std::multiset, std::unordered_set, std::unordered_multiset
Linear algebra	Armadillo, Eigen, Blaze, Blitz++, Boost uBLAS, IT++, dlib
Structs	POD / C / C++ structs via h5cpp-compiler
Arrays	Up to rank 7

v1.12 Highlights

• std::valarray<T> read/write support
• Iterator containers — std::list, std::deque, std::set, std::unordered_set and their multi- variants
• std::complex<T> datasets
• std::float16_t (C++23 IEEE 754 half-precision)
• Rank-7 array support
• Expanded attribute type coverage
• Threaded I/O pipeline for filter chains
• HDF5 1.12.2 ceiling — tested and verified; H5Dvlen_reclaim / reference API compatibility
• Windows MSVC in the CI matrix
• ASan + UBSan clean on Clang 20

Documentation

Full API reference, examples, and architecture notes: vargalabs.github.io/h5cpp

Contributing

See CONTRIBUTING.md for issue naming, branch conventions, commit format, and the pull request workflow.

License

MIT — see LICENSE.