Bellard was born in 1972 in Grenoble, France and went to school in Lycée Joffre (Montpellier), where, at age 17, he created the executable compressor LZEXE.^[2] After studying at École Polytechnique, he went on to specialize at Télécom Paris in 1996.

In 1997, he discovered a new, faster formula to calculate single digits of pi in hexadecimal representation, known as Bellard's formula. It is a variant of the Bailey–Borwein–Plouffe formula.

Bellard's entries won the International Obfuscated C Code Contest three times.^[3] In 2000, he won in the category "Most Specific Output"^[4] for a program that implemented the modular fast Fourier transform and used it to compute the then biggest known prime number, 2^6972593−1 (in the sense that it prints the decimal representation of this number, which itself is assumed to be known).^[5] In 2001, he won in the category "Best Abuse of the Rules" for a tiny compiler (the source code being only 3 kB in size) of a strict subset of the C language for i386 Linux. The program itself is written in this language subset, i.e. it is self-hosting. In 2018, he won in the category "Most inflationary"^[6] for an image decompression program.^[7]

In 2002, he developed TinyGL, a subset of OpenGL suitable for embedded environments.

In 2003, he pushed the first commits of QEMU, developing it solo through v0.7.1 in 2005.^[8]

In 2004, he wrote the TinyCC Boot Loader, which can compile and boot a Linux kernel from source in less than 15 seconds.^[9] In 2005, he designed a system that could act as an Analog or DVB-T Digital TV transmitter by directly generating a VHF signal from a standard PC and VGA card.^[10] In 2011, he created a minimal PC emulator written in pure JavaScript. The emulated hardware consists of a 32-bit x86 compatible CPU, a 8259 Programmable Interrupt Controller, a 8254 Programmable Interrupt Timer, and a 16450 UART.^[11]

On 31 December 2009 he claimed the world record for calculations of pi, having calculated it to nearly 2.7 trillion places in 90 days. Slashdot wrote: "While the improvement may seem small, it is an outstanding achievement because only a single desktop PC, costing less than US$3,000, was used—instead of a multi-million dollar supercomputer as in the previous records."^[12][13] On 2 August 2010 this record was eclipsed by Shigeru Kondo who computed 5 trillion digits, although this was done using a server-class machine running dual Intel Xeon processors, equipped with 96 GB of RAM.

In 2011 he won an O'Reilly Open Source Award.^[14]

In 2014 he proposed the Better Portable Graphics (BPG) image format as a replacement for JPEG.^[15]

In July 2019 he released QuickJS, a small and embeddable JavaScript engine.^[16]

In April 2021, his artificial neural network–based data compressor, NNCP, took first place out of hundreds in the Large Text Compression Benchmark.^[17] The compressor uses Bellard's own artificial neural network library, LibNC ("C Library for Tensor Manipulation"), which is publicly available.^[18]

In August 2023, Bellard released ts_zip, a lossy text compressor using large language models.^[19][20] He updated it in March 2024, making the algorithm considerably faster as well as hardware-independent.^[21]

• PiHex

• Official website
• "Portrait of a Super-Productive Programmer". Archived from the original on 2021-01-28.
• Gocke, Andy; Pizzolato, Nick (May 2009). "ACM Journal Article: Fabrice Bellard". ACM (unspecified). Vol. V, no. N. Archived from the original on 2011-07-26.