This is a list of optimization problem libraries collected from the answers to this question on OR Stack Exchange site.
If you have any suggestions or corrections, especially if I miscategorized something, feel free to make a pull request.
- TSPLIB
- National Traveling Salesman Problems
- VLSI Data Sets: Collection of 102 TSP instances
- Vehicle Routing Problem
- HEC Data
- VRP-REP
- Pickup and Delivery Problems
- Orienteering Problem
- OPLIB: Orienteering Problem
- CVRPLIB: Capacitated Vehicle Routing Problem Library
- Flow shop and Routing Problems
- Flow Shop Sequncing, Job Shop, and Open Shop Scheduling
- Job Shop Scheduling of Taillard's and Demirkol's instances
- UflLib: Uncapacitated Facility Location
- Discrete Location Problems
- CLRLib: Capacitated Location Routing
- QPLIB: A Library of Quadratic Programming Instances
- QAPLIB: Quadratic Assignment Problem Library
- General Mixed Integer Quadratically Constrained Problems
- Biq Mac Library: a Binary Quadratic and Max Cut Library
- Global Optimization Test Problems (Hedar list)
- Global Optimization Test Problems (Neumaier list)
- Handbook of Test Problems in Local and Global Optimization
- Beasley's OR Library
- Bin Packing, Quadratic Assigment, Cutting Stock, Vehicle Routing
- Maximum Clique, Maximum Independent Set, Minimum Vertex Cover, Vertex Coloring
- Atamturk Datasets on fixed-charge flow, lot sizing, mixed-integer knapsack, and more
- OptaPlanner Examples Problem Definitions and Data Sets
- GiC Data Sets
- SIPLIB: Stochastic Integer Programming Test Problems
- Jeff Linderoth, Alex Shapiro, and Stephen Wright
- POSTS: (PO)rtable (S)tochastic programming (T)est (S)et
- Test-Problem Collection for Stochastic Linear Programming (Andy Felt)
- cORe: (c)omputational (O)perations (R)esearch (e)xchange (Suvrajeet Sen)
- WATSON pension fund management test problems
- vOptLib: Multi-Objective Linear Optimization Problems
- Multi-Objective Optimization Repository (MOrepo)
- MIPLIB 2017: Mixed Integer Programming
- MINLPLib: Mixed Integer and Continuous Nonlinear Programming
- CSPlib: Constraint Optimization and Satisfaction
- SIMOPT: (Stochastic) Simulation Optimization Library
- CBLIB: The Conic Benchmark Library
- QBFLIB: Quantified Boolean Formulas
- BASBLib: Bilevel Programming Problems
- COMPlib: COnstraint Matrix Optimization Problem Library
- CUTEr/st: Constrained and Unconstrained (Nonlinear Optimization) Testing Environment
- SDPLIB 1.2, A Library of Semidefinite Programming Test Problems
- NWLPLIB: Wireless Localization
- MIRPLIB: Maritime Inventory Routing Problems
- TTPLib: Train Timetabling Problem Library
- Employee Shift Scheduling
- Graph Partitioning
- Graph Coloring
- Shortest Paths
- Frequency Assignment Problems
- Traveling Umpire Problem
- Combinatorial Auction Test Suite (CATS)