Updates
January 14, 2026
by Rafael Martinelli
The CVRPLib BKS Challenge had a strong start, with 69 new BKSs already found for the 100 XL CVRP instances. Team information is now public, the number of BKSs per team is shown in the score table, and a scheduled maintenance on January 14th (18:00–22:00 UTC) will temporarily freeze the challenge.
January 12, 2026
by Rafael Martinelli
The CVRPLib Best Known Solution (BKS) Challenge has started!
The 30-day competition is now open for submissions on the new XL benchmark set, featuring 100 large-scale CVRP instances with up to 10,000 customers. Teams can submit improved solutions, with real-time leaderboards tracking progress per instance and overall. A technical report describing how the initial BKSs were obtained is available on the Overview page. Registration remains open during the competition.
The 30-day competition is now open for submissions on the new XL benchmark set, featuring 100 large-scale CVRP instances with up to 10,000 customers. Teams can submit improved solutions, with real-time leaderboards tracking progress per instance and overall. A technical report describing how the initial BKSs were obtained is available on the Overview page. Registration remains open during the competition.
January 12, 2026
by Rafael Martinelli
The BKS Challenge starts in just a few hours! Score pages are online, along with "My Submissions" and "My BKSs" for registered users, just below "My Teams". Good luck to all teams and let the challenge begin!
December 12, 2025
by Rafael Martinelli
Team registration for the CVRPLib BKS Challenge is officially open! Teams can now register for the upcoming challenge, which starts in 30 days. The challenge focuses on large-scale CVRP instances and aims to stimulate new ideas in heuristics, hybrid methods, machine learning, and large-scale optimization.
November 11, 2025
by Rafael Martinelli
Official release of the new CVRPLib: The content is the same, but the site now is clearer, working better on both large screens and mobile. It also supports light and dark themes. The plot library has been improved (though very large instances still won’t render). The VRPTW section will be back soon. An instance checker for dataset X is now available — feel free to try it out!
June 21, 2025
by CVRPLib
Proven optimal solutions by Zhengzhong You (University of Florida) and Yu Yang (University of Florida) using RouteOpt exact solver: X-n313-k71 (94043), X-n359-k29 (51505), and X-n384-k52 (65928).
October 15, 2024
by CVRPLib
Proven optimal VRPTW solution by Anthony Karahalios (Carnegie Mellon University) and Willem-Jan van Hoeve (Carnegie Mellon University) using a column elimination approach: C2_10_1 (16841.1).
July 29, 2024
by CVRPLib
July 25, 2024
by CVRPLib
Proven optimal VRPTW solutions by João Marcos Pereira Silva, Eduardo Uchoa, and Anand Subramanian using the Cluster Branching strategy: RC1_4_1 (8522.9), RC1_4_2 (7878.2), R1_4_2 (8873.2), R1_4_5 (9184.6), R1_4_6 (8340.4), C1_6_10 (13617.5).
December 14, 2023
by CVRPLib
Improved solution reported by Keld Helsgaun (Roskilde University) obtained with LKH-3 code for merging the solution from January, 18 2023 (4373245) with the solution from May 3, 2022 (4373320): Flanders2 (4373244).
November 13, 2023
by CVRPLib
Proven optimal solution by Zhengzhong You (University of Florida), Yu Yang (University of Florida), Xinshang Wang (Alibaba Group US), and Wotao Yin (Alibaba Group US) using RouteOpt exact solver: X-n294-k50 (47161).
October 25, 2023
by CVRPLib
Proven optimal VRPTW solutions by João Marcos Pereira Silva and Eduardo Uchoa using VRPSolver with a new cluster branching strategy: C2_2_4 (1695), RC2_2_10 (1989.2).
September 14, 2023
by CVRPLib
Proven optimal CVRP and VRPTW solutions by João Marcos Pereira Silva and Eduardo Uchoa using VRPSolver with a new cluster branching strategy: RC1_2_9 (3073.3), RC1_2_10 (2990.5), X-n344-k43 (42050), X-n351-k40 (25896), X-n367-k17 (22814), and X-n670-k130 (146332).
June 26, 2023
by CVRPLib
Improved VRPTW solutions reported by Simen T. Vadseth, Henrik Andersson, Jean-François Cordeau, and Magnus Stålhane: R1_6_4 (15720.8), R1_8_3 (29301.2), R1_8_5 (33494.0), R1_8_10 (30918.3), R2_8_1 (24963.8), R2_8_5 (22795.6), R2_8_8 (12611.6), C1_10_8 (41648.0), R1_10_1 (53026.1), R1_10_2 (48261.6), R1_10_3 (44673.3), R1_10_6 (46928.2), R2_10_4 (17811.4), R2_10_8 (17403.7), RC1_10_1 (45790.7), RC1_10_3 (42121.9), RC1_10_6 (44898.2), RC1_10_7 (44409.0), RC1_10_9 (43858.0), RC2_10_4 (15654.7).
June 5, 2023
by CVRPLib
Improved VRPTW solutions reported by Niels Wouda, Leon Lan, and Wouter Kool using PyVRP solver: C1_10_3 (40060.0), C2_8_4 (10639.6), R1_4_2 (8873.2), R1_4_3 (7781.6), R1_4_9 (8673.8), R1_6_2 (18519.8), R2_4_10 (5638.1), R2_6_4 (7914.5), R2_6_7 (9770.3), R2_8_10 (19964.2), R2_8_1 (24968.8), R2_8_3 (17229.5), R2_8_4 (13152.8), R2_8_5 (22798.2), R2_8_7 (16351.2), RC1_6_1 (16944.2), RC1_8_1 (29952.8), RC1_8_6 (29148.7), RC1_8_7 (28734.0), RC1_8_8 (28390.0), RC1_8_9 (28331.6), RC2_10_7 (24391.4), RC2_10_8 (23279.8), RC2_8_6 (17190.6), RC2_8_9 (15177.2).
May 28, 2023
by CVRPLib
Improved VRPTW solutions reported by Niels Wouda, Leon Lan, and Wouter Kool using PyVRP solver: C2_8_4 (10641.9), R1_6_2 (18554.4), R2_6_7 (9774.1), R2_8_10 (19977.7), RC1_6_1 (16952.3), RC1_8_7 (28781.0), RC2_10_10 (21731.2), RC2_10_7 (24392.2), RC2_6_10 (8973.3).
January 18, 2023
by CVRPLib
Improved solutions reported by Jørgen Skålnes, Simen T. Vadseth, Henrik Andersson, and Magnus Stålhane from NTNU using a branch-and-cut embedded matheuristic: Brussels2 (345468), Flanders1 (7240118), Flanders2 (4373245).
January 18, 2023
by CVRPLib
Proven optimal VRPTW solutions by João Marcos Pereira Silva and Eduardo Uchoa using VRPSolver with a new cluster branching strategy: C1_10_1 (42444.8), C1_10_5 (42434.8), C1_10_6 (42437.0), C1_6_1 (14076.6), C1_6_2 (13948.3), C1_6_3 (13756.5), C1_6_4 (13538.6), C1_6_5 (14066.8), C1_6_6 (14070.9), C1_6_7 (14066.8), C1_6_8 (13991.2), C1_6_9 (13664.5), C1_8_1 (25156.9), C1_8_5 (25138.6), C1_8_6 (25133.3), C1_8_7 (25127.3). For instance C1_6_3, the optimal solution found was an improved one.
January 5, 2023
by CVRPLib
Improved solution obtained by Mariá C.V. Nascimento (Universidade Federal de São Paulo) and Vinícius R. Máximo (Universidade Federal de São Paulo): Flanders2 (4373316).
December 15, 2022
by CVRPLib
Improved VRPTW solutions reported by Piotr Sielski, Piotr Cybula, Mariusz Kok, Przemysław Pełka, Marek Rogalski (Otimo, and University of Łódź, Poland): C1_10_2 (41337.8), C1_8_8 (24809.7), C2_8_4 (10650.0), R1_10_1 (53046.5), R1_4_5 (9184.6), R1_6_5 (19294.9), R1_6_9 (18474.1), R1_8_1 (36345.0), R2_10_10 (29840.5), R2_10_6 (29124.7), R2_8_10 (19984.8), R2_8_3 (17234.8), R2_8_7 (16357.5), RC1_8_10 (28168.5), RC1_8_1 (29978.9), RC1_8_2 (28290.1), RC1_8_3 (27447.7), RC1_8_4 (26557.2), RC1_8_5 (29219.9), RC1_8_6 (29194.2), RC1_8_7 (28788.6), RC1_8_8 (28418.1), RC1_8_9 (28347.1), RC2_10_10 (21736.1), RC2_10_3 (19618.1), RC2_10_7 (24395.8), RC2_10_8 (23280.2), RC2_8_10 (14370.9), RC2_8_6 (17195.1), RC2_8_9 (15183.0).