- New release
- Binaries of the Typescript and Babel compilers compiled with
QuickJS are available in the download section
including modules, asynchronous generators and proxies.
It optionally supports mathematical extensions such as big integers
(BigInt), big floating point numbers (BigFloat) and operator
- Small and easily embeddable: just a few C files, no external
dependency, 190 KiB of x86 code for a simple hello world
- Fast interpreter with very low startup time: runs the 69000 tests
of the ECMAScript Test
Suite in about 95 seconds on a single core of a desktop PC. The
complete life cycle of a runtime instance completes in less than 300
support including modules, asynchronous generators and full Annex B
support (legacy web compatibility). Many features from the
specification are also supported.
- Passes nearly 100% of the ECMAScript Test Suite tests when selecting the ES2019 features.
- Garbage collection using reference counting (to reduce memory usage
and have deterministic behavior) with cycle removal.
- Mathematical extensions: BigInt, BigFloat, operator overloading, bigint mode, math mode.
- Small built-in standard library with C library wrappers.
An online demonstration of the QuickJS engine with its mathematical
extensions is available
at numcalc.com. It was compiled from
C to WASM/asm.js with Emscripten.
qjs and qjscalc can be run in JSLinux.
QuickJS documentation: HTML version,
Specification of the JS Bignum Extensions: HTML
version, PDF version.
QuickJS embeds the following C libraries which can be used in other
- libunicode: small unicode library supporting case
conversion, unicode normalization, unicode script queries, unicode
general category queries and all unicode binary properties.
- libbf: small library implementing arbitrary precision
IEEE 754 floating point operations and transcendental functions with
exact rounding. It is maintained as a separate project.
QuickJS is released under
the MIT license.
Unless otherwise specified, the QuickJS sources are copyright Fabrice
Bellard and Charlie Gordon.
Fabrice Bellard - https://bellard.org/