Single-file public-domain/open source libraries with minimal dependencies

I am the author of a large number of single-file C/C++ public domain libraries. I am not the only person who writes libraries like this, so below are other, similar libraries.

Generally, the following is a list of small, easy-to-integrate, portable libraries which are usable from C and/or C++, and should be able to be compiled on both 32-bit and 64-bit platforms. However, I have not personally verified that any specific lilbrary is as advertised, or is quality software.

Rules

• Libraries must be usable from C or C++, ideally both
• Libraries should be usable from more than one platform (ideally, all major desktops and/or all major mobile)
• Libraries should compile and work on both 32-bit and 64-bit platforms
• Libraries should use at most two files (one header, one source)

Exceptions will be allowed for good reasons.

Recent additions

Recent additions are marked with an asterisk in the left column.

New libraries and corrections

See discussion after the list.

JSON Parsing

There are a lot of JSON parsers listed here. For some analysis and performance results, check out https://github.com/miloyip/nativejson-benchmark

Other lists

Also you might be interested in other related, but different lists:

• clib: list of (mostly) small single C functions (licenses not listed)
• CCAN: package of lots of shareable C functions (mixed licenses)

Library listing

Public domain single-file libraries usable from C and C++ are in bold. Other libraries are either non-public domain, or two files, or not usable from both C and C++, or all three. Libraries of more than two files are mostly forbidden.

For the API column, "C" means C only, "C++" means C++ only, and "C/C++" means C/C++ usable from either; some files may require building as C or C++ but still qualify as "C/C++" as long as the header file uses extern "C" to make it work. (In some cases, a header-file-only library may compile as both C or C++, but produce an implementation that can only be called from one or the other, because of a lack of use of extern "C"; in this case the table still qualifies it as C/C++, as this is not an obstacle to most users.)

Categories:

• general purpose
  • data structures
  • string processing
  • scripting
  • hashing
• mathematics
  • vector math
  • geometry math
  • general math
• parsing
  • JSON
  • YAML
  • CSV
  • other serialization
  • argv argument processing
  • other parsing
• graphics
  • textmode
  • 2D graphics
  • 3D graphics
  • 3D geometry file processing
  • image loading, saving, & processing
• audio/video/data compression
  • compression
  • audio processing & files
  • video
• videogames
• operating system features
  • files and filenames
  • multithreading
  • networking
  • hardware interfacing
• debugging, profiling, testing
  • debugging
  • profiling
  • unit testing etc.
• other
  • AI
  • cryptography
  • user interface
  • miscellaneous

AI

library	license	API	files	description
Genann	zlib	C/C++	2	simple neural networks (ANN)
KANN	MIT	C/C++	2	automatic differentiation (2 files)
micropather	zlib	C++	2	pathfinding with A*

argv

library	license	API	files	description
Argh!	BSD	C++	1	command-line argument parsing
Clara	Boost	C++	1	composable, command line parser for C++ 11 and beyond
CLI11	BSD	C++	1	Feature-rich CLI parsing in modern C++11
cmdline	BSD	C++	1	command-line argument parsing
flags	public domain	C++	1	command-line argument parsing
kgflags	MIT	C/C++	1	command-line argument parsing
linkom	MIT	C/C++	1	command-line argument parsing w/ DOS-style options
optionparser	MIT	C++	1	command-line argument parsing
parg	public domain	C	2	command-line argument parsing
ProgramOptions.hxx	MIT	C++	1	command-line argument parsing

audio

library	license	API	files	description
aw_ima.h	MIT	C/C++	1	IMA-ADPCM audio decoder
btac1c	MIT	C/C++	1	MS-IMA_ADPCM variant
dr_flac	public domain	C/C++	1	FLAC audio decoder
dr_wav	public domain	C/C++	1	WAV audio loader
Geneva	MIT	C/C++	1	Library generating 8-bit waveforms of various kinds
minimp3	CC0	C	1	Minimalistic MP3 decoder with sse/neon support
miniaudio	public domain	C/C++	1	Audio playback and capture library
pocketmod	MIT	C/C++	1	ProTracker MOD file renderer
sts_mixer	public domain	C/C++	1	simple stereo audio mixer
tinysound	zlib	C/C++	1	direct sound audio mixer & WAV loader
TinySoundFont	MIT	C/C++	1	SoundFont2 loader & synthesizer

compression

library	license	API	files	description
dmc_unrar	GPLv2+	C/C++	1	RAR file decompression
fastlz	MIT	C/C++	2	fast but larger LZ compression
lz4	BSD	C/C++	2	fast but larger LZ compression
miniz.c	MIT	C/C++	1	compression, decompression, ZIP file, PNG writing
microtar	MIT	C/C++	2	lightweight tar library
pithy	BSD	C/C++	2	fast but larger LZ compression

crypto

library	license	API	files	description
Monocypher	public domain	C	2	high-quality small cryptography library
TweetNaCl	public domain	C	2	high-quality tiny cryptography library

data structures

library	license	API	files	description
avl	public domain	C/C++	2	AVL tree
c-bool-value	WTFPLv2	C/C++	1	Simple and easy boolean values in standard c
chobo-shl	MIT	C++	1	several C++11 standard contaner like libraries and helpers
DG_dynarr.h	public domain	C/C++	1	typesafe dynamic arrays (like std::vector) for plain C
DynaVar	GPL-3.0	C++	1	Object which can store any type of primitive data type
klib	MIT	C/C++	2	many 2-file libs: hash, sort, b-tree, etc
libpqueue	BSD	C/C++	2	priority queue (heap)
minilibs	public domain	C	2	two-file binary tress (also regex, etc)
PackedArray	WTFPLv2	C	2	memory-efficient array of elements with non-pow2 bitcount
simclist	BSD	C/C++	2	linked-list
selist	ISC	C/C++	2	space-efficient linked-list
mempool	MIT	C++	1	Efficient minimal memory pool implementation for C++
uthash	BSD	C/C++	2	several 1-header, 1-license-file libs: generic hash, list, etc

debugging

library	license	API	files	description
dbgtools	zlib	C/C++	2	cross-platform debug util libraries
debug-assert	zlib	C++	1	modular assertion macro
debugbreak	BSD	C/C++	1	programmatic debug break
loguru	public domain	C++	1	flexible logging
pempek_assert.cpp	WTFPLv2	C++	2	flexible assertions

files & filenames

library	license	API	files	description
DG_misc.h	public domain	C/C++	1	Daniel Gibson's stb.h-esque cross-platform helpers: path/file, strings
dirent	MIT	C/C++	1	dirent for Windows: retrieve file & dir info
tfile	MIT	C++	1	FILE* wrapper does read-write-append-seek-close (Win/Mac/Unix)
TinyDir	BSD	C	1	cross-platform directory reading (Win/POSIX/MinGW)
tinyfiles	zlib	C/C++	1	cross-platform directory reading (Win/Mac/Unix)
whereami	WTFPLv2	C/C++	2	get path/filename of executable or module

geometry file

library	license	API	files	description
cgltf	MIT	C	1	glTF 2.0 file loader
fast_obj.h	MIT	C	1	wavefront OBJ file loader
objzero	MIT	C	2	wavefront OBJ file loader
tinyply	public domain	C++	2	PLY mesh file loader
tinyobjloader	MIT	C++	1	wavefront OBJ file loader
tinyobjloader-c	MIT	C	1	wavefront OBJ file loader
tk_objfile	MIT	C/C++	1	OBJ file loader
yocto_obj.h	MIT	C/C++	1	wavefront OBJ file loader

geometry math

library	license	API	files	description
Clipper	Boost	C++	2	line & polygon clipping & offsetting
df	public domain	C/C++	1	find voronoi region in linear time of size of lattice
jc_voronoi	MIT	C/C++	1	find voronoi regions on float/double data
nanoflann	BSD	C++	1	build KD trees for point clouds
nv_voronoi.h	public domain	C/C++	1	find voronoi regions on lattice w/ integer inputs
par_msquares	MIT	C/C++	1	convert (binarized) image to triangles
par_shapes	MIT	C/C++	1	generate various 3d geometric shapes
PolyPartition	MIT	C++	2	polygon triangulation, partitioning
rjm_mc.h	public domain	C/C++	1	marching cubes triangulator
sobol.h	public domain	C/C++	1	sobol & stratified sampling sequences
sdf.h	MIT	C/C++	1	compute signed-distance field from antialiased image
Tomas Akenine-Moller snippets	public domain	C/C++	2	various 3D intersection calculations, not lib-ified
Voxelizer	MIT	C/C++	1	convert triangle mesh to voxel triangle mesh
xatlas	MIT	C++	2	mesh parameterization
yocto_bvh.h	MIT	C/C++	1	ray-casting and closest-element queries of bounding-volume hierarchy
yocto_shape.h	MIT	C/C++	1	shape generation, tesselation, normals, etc.

graphics (text)

library	license	API	files	description
rang	public domain	C++	1	cross-platform colored console text

graphics (2d)

library	license	API	files	description
blendish	MIT	C/C++	1	blender-style widget rendering using NanoVG
Cimg	CeCILL/CeCILL-C	C++	1	image processing toolkit (60K LoC)
Immediate2D	public domain	C++	2	zero-configuration, immediate-mode 2D graphics for Windows
noc_turtle	MIT	C/C++	2	procedural graphics generator
tigr	public domain	C/C++	2	quick-n-dirty window text/graphics for Windows and macOS

graphics (3d)

library	license	API	files	description
debug-draw	public domain	C++	1	API-agnostic immediate-mode debug rendering
lightmapper	public domain	C/C++	1	use your OpenGL renderer to offline bake lightmaps
mikktspace	zlib	C/C++	2	compute tangent space for normal mapping
rjm_raytrace.h	public domain	C/C++	1	minimalistic SSE packet raytracer for offline baking
seamoptimizer	public domain	C/C++	1	modify lightmap data to hide seams
sokol_gfx.h	MIT	C/C++	1	cross-platform 3D API wrapper (GLES2+3/GL3/D3D11/Metal)
Swarmz	public domain	C++	1	swarming/flocking algorithm
tinygizmo	public domain	C++	2	gizmo objects for interactively editing 3d transformations
Vertex Cache Optimizer	public domain	C/C++	1	vertex cache optimization of meshes
Vulkan Memory Allocator	MIT	C/C++	1	memory allocator for Vulkan
yocto_trace.h	MIT	C/C++	1	physically-based unidirectional path tracer w/ MIS for direct lights
yocto_symrigid.h	MIT	C/C++	1	rigid body simulator (sequential impulse/PGS) with support for concave objects

hardware

library	license	API	files	description
EasyTab	public domain	C/C++	1	multi-platform tablet input
libue	MIT	C/C++	1	Helper library for Linux device hot-plug event

hashing

library	license	API	files	description
xxHash	BSD	C/C++	2	fast hash function

images

library	license	API	files	description
EXR miniexr	public domain	C++	2	OpenEXR writer, needs header file
EXR tinyexr	BSD	C/C++	1	EXR image read/write, uses miniz internally
GIF gif.h	public domain	C++	1	animated GIF writer (can only include once)
GIF gif_load	public domain	C/C++	1	(animated) GIF reader
GIF jo_gif.cpp	public domain	C++	1	animated GIF writer (CPP file can also be used as H file)
JPG jpeg-compressor	public domain	C++	2	2-file JPEG compress, 2-file JPEG decompress
JPG NanoJPEG	MIT	C/C++	1	JPEG decoder
JPG tiny_jpeg.h	public domain	C/C++	1	JPEG encoder
JPG EXIF easyexif	MIT	C++	2	EXIF metadata extractor for JPEG images
JPG EXIF TinyEXIF	BSD	C++	2	Parse EXIF data from JPEG (XMP w/ TinyXML2 lib)
PDF PDFgen	public domain	C	2	PDF writer
PNG lodepng	zlib	C/C++	2	PNG encoder/decoder
PNG picopng.cpp	zlib	C++	2	tiny PNG loader
PNG TinyPngOutput	LGPLv3	C/C++	2	PNG writer
PNM PNM	Apache 2.0	C++	1	PBM, PGM and PPM reader and writer
SVG nanoSVG	zlib	C/C++	1	1-file SVG parser; 1-file SVG rasterizer
cro_mipmap.h	public domain	C/C++	1	average, min, max mipmap generators
rjm_texbleed.h	public domain	C/C++	1	Fills in the color of pixels where alpha==0

math

library	license	API	files	description
amoeba	MIT	C/C++	1	constraint solver (Cassowary) w/Lua binding
fft	public domain	C++	1	Fast Fourier Transform
PoissonGenerator.h	MIT	C++	1	Poisson disk points generator (disk or rect)
prns.h	public domain	C/C++	1	seekable pseudo-random number sequences
rnd.h	public domain	C/C++	1	pseudo-random number generation
ShaderFastLibs	MIT	C++	1	(also HLSL) approximate transcendental functions optimized for shaders (esp. GCN)
simrank.hpp	MIT	C++	2	SimRank graph similarity algorithm
SummedAreaTable	MIT	C++	1	Summed-Area Table generation and sum/avg queries
TinyExpr	zlib	C	2	evaluation of math expressions from strings

multithreading

library	license	API	files	description
bikeshed.h	MIT	C/C++	1	cross-platform lock free fixed memory hierarchical work scheduler
mm_sched.h	zlib	C/C++	1	cross-platform multithreaded task scheduler based on enkiTS
thread.h	public domain	C/C++	1	cross-platform thread primitives
TinyCThread	zlib	C/C++	2	cross-platform implementation of the C11 Threads API
TinyThread++	zlib	C++	2	cross-platform implementation of the C++11 Threads API

network

library	license	API	files	description
civetweb	MIT	C/C++	2	HTTP server, fork of Mongoose
EWS	BSD	C/C++	1	HTTP server
happyhttp	zlib	C++	2	HTTP client requests
http	public domain	C/C++	1	HTTP get/post
libcluon	MPL-2.0	C++	1	cross-platform socket wrapper and data marshalling with native implementations for Protobuf, LCM/ZCM, JSON, and MsgPack serialization/deserialization
LUrlParser	MIT	C++	2	lightweight URL & URI parser RFC 1738, RFC 3986
mm_web.h	BSD	C/C++	1	lightweight webserver, fork of webby
mongoose	GPLv2	C/C++	2	HTTP server
par_easycurl.h	MIT	C/C++	1	cURL wrapper
sts_net	public domain	C/C++	1	cross-platform socket wrapper (socket sets and packet API)
yocto	public domain	C/C++	2	non-production-use HTTP server
zed_net	public domain	C/C++	1	cross-platform socket wrapper
znet	MIT	C/C++	1	cross-platform networking w/ Lua binding

serialization

library	license	API	files	description
archive	public domain	C++	1	binary serialize & deserlize w/ STL support
libcluon	MPL-2.0	C++	1	cross-platform data serialization/deserialization with native implementations for Protobuf, LCM/ZCM, JSON, and MsgPack

json

library	license	API	files	description
ajson	Boost	C++	1	JSON serialize & deserialize w/ STL support
cJSON	MIT	C/C++	1	JSON parser
json.h	public domain	C/C++	2	JSON parser
json.hpp	MIT	C++	1	JSON parse, serialize, deserialize
jzon.h	MIT	C++	2	JSON parser
PicoJSON	BSD	C++	1	JSON parse/serializer
parson	MIT	C/C++	2	JSON parser and serializer

yaml

library	license	API	files	description
mini-yaml	MIT	C++	2	YAML parser and serializer

csv

library	license	API	files	description
CSVstream	MIT	C++	1	CSV parser
Fast C++ CSV Parser	BSD	C++	1	CSV parser
Rapidcsv	BSD	C++	1	CSV parser
Vince's CSV Parser	MIT	C++	1	CSV parser and serializer

parsing

library	license	API	files	description
cmp	MIT	C/C++	2	MessagePack parser and serializer
inih	BSD	C/C++	2	.ini file parser
ini.h	public domain	C/C++	1	.ini file parser
minilibs	public domain	C	2	two-file regex (also binary tree, etc)
mm_lexer.h	zlib	C/C++	1	C-esque language lexer
SLRE	GPLv2	C/C++	1	regular expression matcher
tinymemfile	zlib	C++	1	fscanf on in-memory files

profiling

library	license	API	files	description
MicroProfile	public domain	C++	2-4	CPU (and GPU?) profiler, 1-3 header files, uses miniz internally
prof	MIT	C/C++	1	profiler for Linux
Remotery	Apache 2.0	C/C++	2	CPU/GPU profiler Win/Mac/Linux, using web browser for viewer

scripting

library	license	API	files	description
Duktape	MIT	C	2	embeddable JavaScript engine
MY-BASIC	MIT	C	2	interpreter for a BASIC dialect scripting language
LIL	zlib	C/C++	2	interpreter for a Tcl-like scripting language
lualite	MIT	C++	1	generate Lua bindings in C++
Picol	BSD	C/C++	1	interpreter for a Tcl-like scripting language
s7	BSD	C/C++	2	interpreter for a subset of Scheme (R5RS/R7RS)

strings

library	license	API	files	description
dfa	MIT	C/C++	2	fast UTF-8 decoder (need a header file)
DG_misc.h	public domain	C/C++	1	Daniel Gibson's stb.h-esque cross-platform helpers: path/file, strings
gb_string.h	public domain	C/C++	1	dynamic strings
Obfuscate	public domain	C++	1	Guaranteed compile-time string literal obfuscation library for C++14
inja.hpp	MIT	C++	1	template engine
strpool.h	public domain	C/C++	1	string interning
str_view.hpp	MIT	C++	1	null-termination-aware string-view class
utf8	public domain	C/C++	1	UTF-8 string library

unit testing

library	license	API	files	description
catch	Boost	C++	1	unit testing
catch2	Boost	C++	1	unit testing
doctest	MIT	C++	1	unit testing
fctx	BSD	C/C++	1	unit testing
greatest	iSC	C	1	unit testing
hippomocks	LGPL	C++	1	unit testing
labrat	public domain	C/C++	1	unit testing
minctest	zlib	C	1	unit testing
munit	MIT	C	1	unit testing
SPUT	BSD	C/C++	1	unit testing
trompeloeil	Boost	C++	1	unit testing
utest	MIT	C/C++	1	unit testing
utest.h	public domain	C/C++	1	unit testing

user interface

library	license	API	files	description
dear imgui	MIT	C++	9	an immediate-mode GUI formerly named "ImGui"; 3rd-party C wrapper
libcmdf	public domain	C	1	a small library for writing CLI applications
linenoise	BSD	C/C++	2	terminal readline w/ history etc
noc_file_dialog.h	MIT	C/C++	1	file open/save dialogs (Win/Mac/Linux)
nuklear	public domain	C/C++	1	minimal GUI toolkit
tinyfiledialogs	ZLIB	C/C++	2	modal dialogs inc. file open/save (Win/Mac/Linux)
wcwidth9	Apache 2.0	C	1	platform independent wcwidth with full unicode 9 support

vectors

library	license	API	files	description
algebra3.h	public domain	C++	1	vector utilities for 2, 3, and 4 element vectors, all inline
ccVector.h	public domain	C/C++	1	Vector, quaternion and matrix math
gb_math	public domain	C/C++	1	Vector, quaternion and matrix math w/o math.h
Handmade Math	public domain	C/C++	1	vector math
linalg.h	public domain	C++	1	vector/matrix/quaternion math
linalg	ISC	C/C++	1	vector/matrix/quaternion math
mm_vec.h	BSD	C/C++	1	SIMD vector math

video

library	license	API	files	description
jo_mpeg	public domain	C++	1	MPEG file writer

videogames

library	license	API	files	description
app.h	public domain	C/C++	1	Windows-only-but-meant-to-be-cross-platform game-ish framework

miscellaneous

library	license	API	files	description
ASAP	MIT	C++	1	library for parsing, printing, iterating and operating on dates.
cpp-generators	BSD	C++	1	generators in C++
Hedley	public domain	C/C++	1	compiler portability, optimization, static analysis, etc.
levenshtein	MIT	C/C++	2	compute edit distance between two strings
MakeID.h	public domain	C++	1	allocate/deallocate small integer IDs efficiently
openGA	MPL-2.0	C++	1	A C++ Generic Algorithm solver library
picobench	MIT	C++	1	microbenchmarking
PlusCallback	zlib	C++	1	function/method callbacks
process.h	public domain	C/C++	1	process control API
random	MIT	C++	1	convenient API for random
sokol_time.h	MIT	C/C++	1	cross-platform time measurement
stmr	MIT	C	2	extract English word stems
tinyformat	Boost	C++	1	typesafe printf
tinytime	zlib	C/C++	1	quick-and-dirty time elapsed time
visit_struct	Boost	C++	2	struct-field reflection

There are also these XML libraries, but I am so significantly not a fan of XML that I've consigned these to the basement to make you think twice.

• parsing: tinyxml2: XML (zlib license)
• parsing: pugixml: XML (MIT license)
• parsing: yxml: XML (MIT license)

New libraries and corrections

Submissions of new libraries: I accept submissions (as issues or as pull requests). Please note that every file that must be included in a user's project counts; a header and a source file is 2 files, but a header file, source file, and LICENSE (if the license isn't in the source file) is 3 files, and won't be accepted, because it's not 2 files. But actually 'LICENSE' is a problem for just dropping the library in a source tree anyway, since it's not scoped to just the library, so library authors are encouraged to include the license in the source file and not require a separate LICENSE.

Corrections: if information for a library above is wrong, please send a correction as an issue, pull request, or email. Note that if the list indicates a library works from both C/C++, but it doesn't, this could be an error in the list or it could be a bug in the library. If you find a library doesn't work in 32-bit or 64-bit, the library should be removed from this list, unless it's a bug in the library.

List FAQ

Can I link directly to this list?

Yes. This is the preferred link.

Why isn't library XXX which is made of 3 or more files on this list?

I draw the line arbitrarily at 2 files at most. (Note that some libraries that appear to be two files require a separate LICENSE file, which made me leave them out). Some of these libraries are still easy to drop into your project and build, so you might still be ok with them. But since people come to stb for single-file public domain libraries, I feel that starts to get too far from what we do here.

Why isn't library XXX which is at most two files and has minimal other dependencies on this list?

Probably because I don't know about it, feel free to submit a pull request, issue, email, or tweet it at me (it can be your own library or somebody else's). But I might not include it for various other reasons, including subtleties of what is 'minimal other dependencies' and subtleties about what is 'lightweight'.

Why isn't SQLite's amalgamated build on this list?

Come on.