Jeffrey Spencer

Born : 1974 Cat. M50 Ultrarunner since 2009

DUV-index ?Largest integer N such that the runner has at least N credited races of at least N km.

DUV-index+ ?Largest integer N such that the race distances provide at least N complete segments of N km in total. A single long race may therefore contribute several segments. See the DUV-Index tab for the detailed calculation. calculation details

Countries visited ?

United States

7,0%

Rank quotient ?This runner's calculation uses 63 eligible race(s): Σ(rank − 1) = 1 377; Σ finishers = 19 570. 1 377 / 19 570 × 100 = 7.04%. A win adds 0 to the numerator. Lower is better.

Totals

Ultras completed63

Km — ultra races3 658 km

Longest race80,5 km

63rd JFK 50 Mile — 22/11/2025

Km per year (ultra races)

309

2022

426

2023

130

2024

229

2025

2026

Race types (share of distance)

Trail100,0%

Wins & podiums (ultra)

🏆 Win1

🏆 Win M2

🏅 Top 312

🏅 Top 3 M13

Longest winning streak1

Current streak0

Records

50 km4h00'34 50 mi7h15'43 6 h59,14 km

HISTORY

63 race(s)

Date		Race	Perf.	Rk
2026
22.03	6h	10th Miocene Epic 6 Hour Endurance Challenge	56.327 km	2 🥈
2025
22.11	50mi	63rd JFK 50 Mile	7:50:50 h	105
25.10	50km	12th Patapsco Valley 50K	5:25:20 h	10
31.05	50km	11th Worlds End Ultramarathon 50K	6:43:26 h	18
29.03	6h	9th Miocene Epic 6 Hour Endurance Challenge	48.087 km	3 🥉
2024
23.11	50mi	62nd JFK 50 Mile	7:39:55 h	82
19.10	50km	11th Patapsco Valley 50K	5:20:32 h	13
2023
18.11	50mi	61st JFK 50 Mile	7:32:09 h	58
21.10	50km	10th Patapsco Valley 50K	5:40:09 h	14
09.09	50km	8th Boulder Field 100 - 50 km Ultra Run	5:17:44 h	10
19.08	50km	8th MD Heat Trail Race	5:36:05 h	10
03.06	50km	11th Cayuga Trails 50 km Race	6:03:24 h	13
22.04	50km	11th Hyner View Trail Challenge 50 km	5:55:46 h	51
11.03	28mi	18th Seneca Creek Greenway Trail 28 Mile	4:22:04 h	2 🥈
14.01	50km	11th PHUNT 50K Run	4:49:39 h	4
2022
29.10	50km	9th Patapsco Valley 50K	5:36:25 h	24
10.09	50km	7th Boulder Field 100 - 50 km Ultra Run	4:58:26 h	13
04.06	50km	8th Worlds End Ultramarathon 50K	5:58:01 h	7
23.04	50km	10th Hyner View Trail Challenge 50 km	5:44:27 h	32
26.03	6h	6th Miocene Epic 6 Hour Endurance Challenge	58.580 km	4
15.01	50km	10th PHUNT 50K Run	5:05:36 h	7
2021
13.11	50mi	12th Stone Mill 50 Mile Run	8:21:33 h	5
30.10	50km	8th Patapsco Valley 50K	5:28:51 h	9
05.06	50km	7th Worlds End Ultramarathon 50K	6:07:17 h	8
24.04	50km	9th Hyner View Trail Challenge 50 km	6:01:48 h	28
27.03	6h	5th Miocene Epic 6 Hour Endurance Challenge	58.580 km	3 🥉
2020
28.10	50km	7th Patapsco Valley 50K	5:07:44 h	4
12.09	50km	5th Boulder Field 100 - 50 km Ultra Run	4:28:21 h	2 🥈
2019
23.11	50mi	57th JFK 50 Mile	7:15:43 h	37
26.10	50km	6th Patapsco Valley 50K	4:53:01 h	3 🥉
17.08	50km	6th MD Heat Trail Race	5:28:19 h	1 🏆
01.06	50km	5th Worlds End Ultramarathon 50K	6:12:06 h	4
30.03	6h	3rd Miocene Epic 6 Hour Endurance Challenge	59.143 km	2 🥈
02.03	28mi	15th Seneca Creek Greenway Trail 28 Mile	4:13:55 h	2 🥈
2018
17.11	50mi	56th JFK 50 Mile	8:33:39 h	100
27.10	50km	5th Patapsco Valley 50K	4:00:34 h	8
02.06	50km	4th Worlds End Ultramarathon 50K	6:18:25 h	5
10.02	50km	7th Mid-Maryland Ultra 50k	4:00:57 h	3 🥉
2017
18.11	50mi	55th JFK 50 Mile	7:48:55 h	51
28.10	50km	4th Patapsco Valley 50K	5:34:31 h	14
16.09	50km	2nd Boulder Field 100 - 50 km Ultra Run	4:47:54 h	10
26.08	50km	4th MD Heat Trail Race	5:25:25 h	5
03.06	50km	3rd Worlds End Ultramarathon 50K	6:30:05 h	9
2016
19.11	50mi	54th JFK 50 Mile	8:06:17 h	72
22.10	50km	3rd Patapsco Valley 50K	5:03:46 h	20
27.08	50km	3rd MD Heat Trail Race	5:49:58 h	7
23.04	50km	5th Hyner View Trail Challenge 50 km	5:53:01 h	38
05.03	50km	12th Seneca Creek Greenway Trail 50k	4:43:50 h	3 🥉
13.02	50km	5th Mid-Maryland Ultra 50k	4:33:21 h	2 🥈
2015
21.11	50mi	53rd JFK 50 Mile	7:31:27 h	47
18.04	50km	8th Endurance Challenge - Washington D.C. Trail 50 km	4:45:11 h	13
21.03	50km	27th The HAT Run 50K	4:46:55 h	11
2014
22.11	50mi	52nd JFK 50 Mile	8:16:02 h	100
2013
23.11	50mi	51st JFK 50 Mile	7:46:15 h	58
01.06	50km	6th Endurance Challenge - Washington D.C. Trail 50 km	5:09:06 h	14
06.04	50mi	19th Umstead Endurance Run 50 Miles	7:47:45 h	9
2012
17.11	50mi	50th JFK 50 Mile	7:31:08 h	55
02.06	50km	5th Endurance Challenge - Washington D.C. Trail 50 km	4:47:18 h	4
24.03	50km	24th The HAT Run 50K	4:46:55 h	13
2011
19.11	50mi	49th JFK 50 Mile	7:43:32 h	66
19.03	50km	23rd The HAT Run 50K	5:04:17 h	25
2010
20.11	50mi	1st Stone Mill 50 Mile Run	8:43:54 h	7
2009
21.11	50mi	47th JFK 50 Mile	8:01:07 h	81

Filter

Runner	Races in common

DUV-index calculation details

#	Date	Race	Credited km	DUV-index+
✓ 1	22/11/2025	63rd JFK 50 Mile	80,47	×1
✓ 2	23/11/2024	62nd JFK 50 Mile	80,47	×1
✓ 3	18/11/2023	61st JFK 50 Mile	80,47	×1
✓ 4	13/11/2021	12th Stone Mill 50 Mile Run	80,47	×1
✓ 5	23/11/2019	57th JFK 50 Mile	80,47	×1
✓ 6	17/11/2018	56th JFK 50 Mile	80,47	×1
✓ 7	18/11/2017	55th JFK 50 Mile	80,47	×1
✓ 8	19/11/2016	54th JFK 50 Mile	80,47	×1
✓ 9	21/11/2015	53rd JFK 50 Mile	80,47	×1
✓ 10	22/11/2014	52nd JFK 50 Mile	80,47	×1
✓ 11	23/11/2013	51st JFK 50 Mile	80,47	×1
✓ 12	6/4/2013	19th Umstead Endurance Run 50 Miles	80,47	×1
✓ 13	17/11/2012	50th JFK 50 Mile	80,47	×1
✓ 14	19/11/2011	49th JFK 50 Mile	80,47	×1
✓ 15	20/11/2010	1st Stone Mill 50 Mile Run	80,47	×1
✓ 16	21/11/2009	47th JFK 50 Mile	80,47	×1
✓ 17	30/3/2019	3rd Miocene Epic 6 Hour Endurance Challenge	59,14	×1
✓ 18	26/3/2022	6th Miocene Epic 6 Hour Endurance Challenge	58,58	×1
✓ 19	27/3/2021	5th Miocene Epic 6 Hour Endurance Challenge	58,58	×1
✓ 20	22/3/2026	10th Miocene Epic 6 Hour Endurance Challenge	56,33	×1
✓ 21	25/10/2025	12th Patapsco Valley 50K	50,00	×1
✓ 22	31/5/2025	11th Worlds End Ultramarathon 50K	50,00	×1
✓ 23	19/10/2024	11th Patapsco Valley 50K	50,00	×1
✓ 24	21/10/2023	10th Patapsco Valley 50K	50,00	×1
✓ 25	9/9/2023	8th Boulder Field 100 - 50 km Ultra Run	50,00	×1
✓ 26	19/8/2023	8th MD Heat Trail Race	50,00	×1
✓ 27	3/6/2023	11th Cayuga Trails 50 km Race	50,00	×1
✓ 28	22/4/2023	11th Hyner View Trail Challenge 50 km	50,00	×1
✓ 29	14/1/2023	11th PHUNT 50K Run	50,00	×1
✓ 30	29/10/2022	9th Patapsco Valley 50K	50,00	×1
✓ 31	10/9/2022	7th Boulder Field 100 - 50 km Ultra Run	50,00	×1
✓ 32	4/6/2022	8th Worlds End Ultramarathon 50K	50,00	×1
✓ 33	23/4/2022	10th Hyner View Trail Challenge 50 km	50,00	×1
✓ 34	15/1/2022	10th PHUNT 50K Run	50,00	×1
✓ 35	30/10/2021	8th Patapsco Valley 50K	50,00	×1
✓ 36	5/6/2021	7th Worlds End Ultramarathon 50K	50,00	×1
✓ 37	24/4/2021	9th Hyner View Trail Challenge 50 km	50,00	×1
✓ 38	28/10/2020	7th Patapsco Valley 50K	50,00	×1
✓ 39	12/9/2020	5th Boulder Field 100 - 50 km Ultra Run	50,00	×1
✓ 40	26/10/2019	6th Patapsco Valley 50K	50,00	×1
✓ 41	17/8/2019	6th MD Heat Trail Race	50,00	×1
✓ 42	1/6/2019	5th Worlds End Ultramarathon 50K	50,00	×1
✓ 43	27/10/2018	5th Patapsco Valley 50K	50,00	×1
✓ 44	2/6/2018	4th Worlds End Ultramarathon 50K	50,00	×1
✓ 45	10/2/2018	7th Mid-Maryland Ultra 50k	50,00	×1
✓ 46	28/10/2017	4th Patapsco Valley 50K	50,00	×1
✓ 47	16/9/2017	2nd Boulder Field 100 - 50 km Ultra Run	50,00	×1
✓ 48	26/8/2017	4th MD Heat Trail Race	50,00	×1
✓ 49	3/6/2017	3rd Worlds End Ultramarathon 50K	50,00	×1
✓ 50	22/10/2016	3rd Patapsco Valley 50K	50,00	×1
51	27/8/2016	3rd MD Heat Trail Race	50,00	×1
52	23/4/2016	5th Hyner View Trail Challenge 50 km	50,00	×1
53	5/3/2016	12th Seneca Creek Greenway Trail 50k	50,00	×1
54	13/2/2016	5th Mid-Maryland Ultra 50k	50,00	×1
55	18/4/2015	8th Endurance Challenge - Washington D.C. Trail 50 km	50,00	×1
56	21/3/2015	27th The HAT Run 50K	50,00	×1
57	1/6/2013	6th Endurance Challenge - Washington D.C. Trail 50 km	50,00	×1
58	2/6/2012	5th Endurance Challenge - Washington D.C. Trail 50 km	50,00	×1
59	24/3/2012	24th The HAT Run 50K	50,00	×1
60	19/3/2011	23rd The HAT Run 50K	50,00	×1
61	29/3/2025	9th Miocene Epic 6 Hour Endurance Challenge	48,09	—
62	11/3/2023	18th Seneca Creek Greenway Trail 28 Mile	45,06	—
63	2/3/2019	15th Seneca Creek Greenway Trail 28 Mile	45,06	—