General Purpose Factoring Records


Below is a chart of general purpose factoring records going back to 1990. By "general purpose", we mean a factoring algorithms whose running time is dependent upon only the size of the number being factored (i.e. not on the size of the prime factors or any particular form of the number).

Sieving is typically the dominant factorization run time in practice. All sieving times below are approximate. Early versions of factoring records estimated time in MIPS years, which is the number of years it would take a computer that operates at one million instructions per second to factor the number. More recently, almost everybody uses Pentiums or AMDs. Thus, we scale some timings to Pentium 1GHz CPU years: the number of years it would take a 1GHz Pentium (or AMD) to complete sieving.

number digits date completed sieving time algorithm
C116 116 1990 275 MIPS years mpqs
RSA-120 120 June, 1993 830 MIPS years mpqs
RSA-129 129 April, 1994 5000 MIPS years mpqs
RSA-130 130 April, 1996 1000 MIPS years gnfs
RSA-140 140 February, 1999 2000 MIPS years gnfs
RSA-155 155 August, 1999 8000 MIPS years gnfs
C158 158 January, 2002 3.4 Pentium 1GHz CPU years gnfs
RSA-160 160 March, 2003 2.7 Pentium 1GHz CPU years gnfs
RSA-576 174 December, 2003 13.2 Pentium 1GHz CPU years gnfs
C176 176 May, 2005 48.6 Pentium 1GHz CPU years gnfs
RSA-200 200 May, 2005 121 Pentium 1GHz CPU years [*] gnfs
RSA-768 232 Dec, 2009 3,300 Opteron 1GHz CPU years [**] gnfs

[*] In regard to RSA-200, Thorsten Kleinjung writes: we spend 25% of the total time for the matrix step. If one considers the total time we spent about 170 CPU years.

[**] In regard to RSA-768, they sieved twice as much as needed in order to make the matrix more manageable. The matrix time took about one tenth of the sieving time. The total time for the factorization was estimated to be about 4,400 Opteron 1GHz years.

For more factorization results, please see the Factorization Announcements page or Paul Zimmermann's Factor Records page.


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