Pyramid Productions


The aim of MacPrimes is to provide a comprehensive list of prime number search (number crunching) software available for the Mac platform. Many of the applications listed below have been ported to Mac from Windows or Linux by myself, and can be downloaded directly, but others are not, and in the case I try to provide a link to where the software can be downloaded from. Many of these applications are in use by wider prime search projects, and where possible, I provide links to these so you can participate in an existing search, rather than go it alone!

Please search below, applications are listed in alphabetical order. If you think something is missing, or incorrect, please get in touch. Happy crunching!


[AP26] [BOINC] [CWPSieve] [GCWSieve] [Genefer] [LLR] [Phrot] [PPSieve] [PFGW] [Prime95] [PRPNet] [SR2Sieve] [TPSieve]


AP26 searches for Arithmetic Progressions of prime numbers. The code was written by Jaroslaw Wroblewski and Geoff Reynolds, with the Mac port by Iain Bethune.

To date, the largest known progression contains 26 primes, and was found in 2010 by Benoat Perichon using the AP26 software as part of the PrimeGrid Project. Since the discovery of the AP26, no further AP search is ongoing at PrimeGrid, however, you can still use the AP26 application to search for larger AP26, or perhaps an elusive AP27...


AP26_SSE.tar.gz (350KB). Intel 32-bit, 64-bit, SSE-accelerated versions

AP26_PPC.tar.gz (184KB). Intel 32-bit, CUDA 2.3-accelerated version

AP26_CUDA.tar.gz (70KB). PowerPC 32-bit version

Usage: ./AP26_version <kmin> <kmax> <shift> [<linear>]


Not a prime search application per se, but a general framework for distributed computing projects. In particular, one can join the PrimeGrid project, and participate in a range of prime search sub-projects.

Downloads & more information:

BOINC : Berkeley Open Infrastructure for Network Computing



CWPSieve is a CUDA-accelerated sieving program for Generalised Cullen and Woodall primes (n.b^n +/- 1). It is written by Ken Brazier, with the Mac port by Iain Bethune. CWPSieve is used by PrimeGrid's Cullen/Woodall (Sieve) sub-project.


cwpsieve-cuda-0.2.3c.tar.gz (336KB). Intel 32-bit and 64-bit, BOINC-enabled and standalone version 0.2.3c. CUDA 3.2 required.


GCWSieve is the CPU-equivalent of CWPSieve. It is written by Geoff Reynolds, with the Mac port by Iain Bethune. GCWSieve is used by PrimeGrid's Cullen/Woodall (Sieve) sub-project.


gcwsieve_ppc32_1.3.8.tar.gz (104KB). PPC 32-bit BOINC-enabled version 1.3.8.

gcwsieve_ppc64_1.3.8.tar.gz (22KB). PPC 64-bit BOINC-enabled version 1.3.8.

gcwsieve_i686_1.3.8.tar.gz (21KB). Intel 32-bit BOINC-enabled version 1.3.8.

gcwsieve_x86_64_1.3.8.tar.gz (78KB). Intel 64-bit BOINC-enabled version 1.3.8.


Genefer is a program for finding large Generalised Fermat Primes (b^2^n+1), originally written by Yves Gallot in 2001. It has since been updated by David Underbakke and Mark Rodenkirch to provide checkpointing and other features. In addition, David and Mark developed two new versions of Genefer - GenefX64, which uses SSE3 instructions for additional speed, at the expense of a reduced b range, and Genefer80, which uses 80-bit floating point instructions for a larger b range with similar speed to the original Genefer. In Dec 2010, Shoichiro Yamada released GeneferCUDA, allowing GFN tests to be performed by double-precision capable Nvidia GPUs. Mac ports of the Genefers were made by Iain Bethune and are available below. Genefer is used by the various GFN testing ports available on PRPNet


genefer_macintel_2.2.1.tar.gz (18KB). Intel 32-bit version 2.2.1.

genefx64_macintel_2.2.1.tar.gz (16KB). Intel 64-bit version 2.2.1.

genefer80_macintel_2.2.1.tar.gz (12KB). Intel 32-bit version 2.2.1.

genefercuda_macintel_0.97.tar.gz (45KB). Intel 32-bit & 64-bit version 0.97. CUDA 3.2 Required.


LLR, developed by Jean Penné performs primality tests using the Lucas-Lehmer-Reisel method on numbers of the form k.b^n +/- 1 (k < b^n), which includes the Proth and Reisel numbers where b=2. In addition a number of other tests are implemented including PRP tests for a range of less well-known number forms. LLR is based on the gwnum library found in Prime95 developed by George Woltman. The Mac port of LLR is produced by Iain Bethune. LLR is heavily used by Primegrid for a range of prime search sub-projects.


llr_macintel_3.8.6.tar.gz (2MB). Intel 32-bit version 3.8.6

A full range of LLR downloads are available from Jean Penné's page


Phrot is a primality testing program for Proth numbers (k.2^n+1). It can also perform PRP tests on a range of other number forms. Phrot was originally developed by Phil Carmody, and is now maintained by Mark Rodenkirch, who provides the Mac builds. While Phrot can often be beated for performance by other applications such as LLR, it is highly portable, and so is able to be used on architectures besides Intel, such as the PPC and IBM Power platforms. Phrot may be used within PRPNet for certain prime search projects. More details are available on Mark Rodenkirch's site.


phrot_macintel_0.72.tar.gz (82KB). Intel 32-bit version 0.72

phrot_macppc_0.72.tar.gz (74KB). PPC 32-bit version 0.72


PPSieve is a sieving program for Proth and Reisel numbers (k.2^n +/- 1), written by Ken Brazier with Mac Port by Iain Bethune. It was used by Primegrid for the Proth Prime Search sub-project but has since been obsoleted by TPSieve, and is included here mainly for historical interest. CUDA and OpenCL versions are also available for use with NVidia and AMD/ATI graphics cards respectively.


ppsieve_macintel_0.3.10d.tar.gz (218KB). Intel 32-bit and 64-bit version 0.3.10d (BOINC and non-BOINC)

ppsieve_cuda_macintel_0.2.3b.tar.gz (336KB). Intel 32-bit and 64-bit version 0.2.3b (BOINC and non-BOINC, CUDA 3.2 required)


PFGW is powerful primality and PRP testing program for a wide range of number forms. Based on George Woltman's gwnum library, it can perform efficient tests on Intel X86 hardware, although in some cases application optimised for a specific number form may outperform it (e.g. LLR, Genefer, Prime95, PFGW is still very useful for more unusual prime forms, and also for falling back on when other programs reach their limits. PFGW is included in PRPNet, but can also be downloaded from SourceForge. Mac, Windows and Linux versions are available.


pfgw_macintel_3.4.7.tar.gz (4.3MB). Intel 32-bit and 64-bit version 3.4.7

Older versions available on the SourceForge download page


Prime95 is one of the most well-known primality testing program. Developed by George Woltman, Prime95 tests Mersenne numbers (2^P-1, where P is prime) and is used by the Great Internet Mersenne Prime Search (GIMPS) project. In addition, Prime95 is well known as part of stress-testing or benchmarking suites. Prime95 is available for Mac OS X and Windows and the command-line version 'mprime' is available for Linux and BSD clients.

Downloads: (4.0MB). Intel version 26.5

More information and downloads available on the GIMPS website


PRPNet, developed by Mark Rodenkirch, is a client/server program for distributed prime searching. Similar in many ways to BOINC, PRPNet is solely for primality and PRP testing, and is run via the command line only. Nevertheless, it is very easy to set up and provides easy access to a wide range of prime search projects not available in BOINC such as Generalized Fermat Primes, Factorial and Primorial Primes, Generalised Cullen and Woodall Primes, and more! PRPNet makes use of a range of programs, including Genefer, LLR, Phrot, and PFGW, which are distributed along with the client. Instruction for getting started with PRPNet can be found on the PrimeGrid Project Staging Area Forum.


prpclient-4.3.0beta-macintel.7z (1.6MB). Intel version 4.3.0 Beta.

prpclient-4.3.0beta-macppc.7z (181KB). PPC version 4.3.0 Beta.

NB: Both downloads require a program capable of opening 7zip archives, such as Ez7z.


SR2Sieve is a program developed by Geoffrey Reynolds to sieve composite numbers of the forms k*b^n+/-1 or b^n+/-k. It is used by PrimeGrid for a number of sieve sub-projects, including the Prime Sierpinski Problem, Reisel Problem and 321 Prime Search. The Mac port is provided by Iain Bethune. Further information and source code can be found on Geoff's website.

Downloads: (76KB). Intel 32-bit and 64-bit version 1.8.11


TPSieve is a sieving program for Proth and Reisel numbers (k.2^n +/- 1), written by Ken Brazier with Mac Port by Iain Bethune. It replaces PPSieve since it can simultaneously sieve for the + and - forms, making it extremely useful for twin prime searching. TPSieve (and GPU variants) currently used by Primegrid for the Proth Prime Search sub-project. CUDA and OpenCL versions are also available for use with NVidia and AMD/ATI graphics cards respectively.


tpsieve_macintel_0.3.10d.tar.gz (220KB). Intel 32-bit and 64-bit version 0.3.10d (BOINC and non-BOINC)

tpsieve_cuda_macintel_0.2.3b.tar.gz (338KB). Intel 32-bit and 64-bit version 0.2.3b (BOINC and non-BOINC, CUDA 3.2 required)

tpsieve_cuda_macintel_0.2.3e.tar.gz (86KB). Intel 32-bit and 64-bit version 0.2.3e (non-BOINC, OpenCL 1.0 required)

Back to top








Website by Iain Bethune, Graphics © Apple Computer