Coin-HSL Archive



MA27, MA28, MC19 only.

Code Download

Previous releases

Coin-HSL Full



All codes listed below.

Code Download

Previous releases


HSL provides a number of linear solvers that can be used in IPOPT. We provide several different ways for IPOPT users to download our codes.

Free downloads

Are available from the boxes on the right. The personal licence on the HSL Archive package permits commercial use, but not redistribution.

A condition of the licence is that HSL is cited in any resulting publications or presentations:
"HSL. A collection of Fortran codes for large scale scientific computation."

Commercial Licencing

Details of commercial licencing, including incorporation licencing, are available on our licencing page. Alternatively, please contact us at

Which solver?

For general use we recommend HSL_MA97. For small or highly sparse problems use MA57. For huge problems use HSL_MA86 (if factors fit in memory) or HSL_MA77 (if they don't).

SolverFree to allFree to academicsProblem sizeParallelRepeatable answersNotes
MA27YesYesSmallNoYesOut dated, relatively slow
MA57YesSmall / MediumThreaded BLASYes
HSL_MA86YesLargeHighlyNo*Designed for multicore
HSL_MA97YesSmall / Medium / LargeYesYesSlower than HSL_MA86 on large problems

* Note: HSL_MA86 achieves repeatable answers in serial, however when running in parallel operations may be reordered for better performance. This leads to different (but equally valid) solutions.

Performance tips