Lowest GAP factor half marathons — ranked with evidence

Which race ranks first — and why is it Estes Park Marathon and Half Marathon?

Estes Park Marathon and Half Marathon leads this ranking on gap factor (-9.9%).

Compare Estes Park Marathon and Half Marathon vs Montana Marathon (Billings)

Ranked comparison table
#	Race	GAP factor	Ascent	Climb density	Descent	Net elevation	Max absolute grade	Fee	As of
1	Estes Park Marathon and Half Marathon - colorado	-9.9%	61 m	2.9 m/km	539 m	-477 m	21.5%	Unavailable	2026-07-18
2	Montana Marathon (Billings) Half Marathon - montana	-4.2%	73 m	3.5 m/km	266 m	-193 m	11.6%	Unavailable	2026-07-06
3	Bozeman Half Marathon & 10K - montana	-4.2%	67 m	3.2 m/km	249 m	-182 m	6.7%	Unavailable	2026-07-06
4	Spurs Austin International Half (fka 3M Half Marathon) - texas	-2.3%	42 m	2.0 m/km	143 m	-101 m	8.1%	Unavailable	2026-07-06
5	Jack & Jill's Downhill Marathon & Half Half Marathon - washington	-1.5%	311 m	14.7 m/km	574 m	-264 m	31.2%	Unavailable	2026-07-06
6	Trieste Spring Run Half Marathon - italy	-1.5%	63 m	3.0 m/km	134 m	-73 m	20.7%	Unavailable	2026-07-06
7	St. Croix Crossing Half Marathon - minnesota	-1.0%	124 m	5.9 m/km	189 m	-64 m	10.8%	Unavailable	2026-07-06
8	Generali Genève Marathon Half Marathon - switzerland	-1.0%	94 m	4.4 m/km	147 m	-54 m	7.0%	Unavailable	2026-07-06
9	RAD Half Marathon & 10K (Asheville) - north-carolina	-0.9%	135 m	6.4 m/km	206 m	-71 m	11.9%	Unavailable	2026-07-06
10	Great North Run Half Marathon - north-east	-0.6%	80 m	3.8 m/km	111 m	-32 m	6.7%	£68	2026-07-06
11	HooDoo Half Marathon (Fairbanks) - alaska	-0.6%	133 m	6.3 m/km	180 m	-48 m	10.2%	Unavailable	2026-07-06
12	Allianz Richmond Marathon Half Marathon - virginia	-0.5%	89 m	4.2 m/km	126 m	-37 m	8.7%	Unavailable	2026-07-06
13	Hoag OC Marathon Running Festival Half Marathon - california	-0.3%	125 m	5.9 m/km	157 m	-32 m	7.9%	Unavailable	2026-07-06
14	Zurich Rock 'n' Roll Running Series Madrid Half Marathon - spain	-0.3%	124 m	5.9 m/km	151 m	-26 m	11.2%	Unavailable	2026-07-06
15	Windermere Marathon (Spokane) Half Marathon - washington	-0.1%	140 m	6.6 m/km	170 m	-30 m	13.5%	Unavailable	2026-07-06
16	Zürich Marathon Half Marathon - switzerland	-0.0%	21 m	1.0 m/km	23 m	-2 m	2.2%	Unavailable	2026-07-06
17	Cheltenham Running Festival Half Marathon - south-west	0.0%	70 m	3.3 m/km	75 m	-5 m	4.4%	£38	2026-07-06
18	Summer Breeze Half Marathon (San Leandro) - california	0.0%	0 m	0.0 m/km	0 m	-0 m	1.8%	Unavailable	2026-07-06
19	The Woodlands Marathon Half Marathon - texas	0.0%	52 m	2.5 m/km	55 m	-3 m	3.5%	Unavailable	2026-07-06
20	Naturosa Catania Marathon Half Marathon - italy	0.0%	11 m	0.5 m/km	12 m	-0 m	3.1%	Unavailable	2026-07-06
21	Vale of York Half Marathon - yorkshire	0.0%	27 m	1.3 m/km	27 m	0 m	1.8%	£28	2026-07-06
22	Tirol läuft (Innsbruck) Half Marathon - austria	0.0%	40 m	1.9 m/km	42 m	-2 m	5.5%	Unavailable	2026-07-06
23	Medio Maratón de Santander Half Marathon - spain	0.0%	28 m	1.3 m/km	28 m	-0 m	3.2%	Unavailable	2026-07-06
24	Bath & Bristol Railway Races Half Marathon - south-west	0.0%	33 m	1.6 m/km	33 m	1 m	2.4%	£46	2026-07-06
25	The Asheville Marathon & Half Half Marathon - north-carolina	0.1%	260 m	12.3 m/km	322 m	-61 m	12.1%	Unavailable	2026-07-06
26	Idaho Falls Marathon Half Marathon - idaho	0.1%	50 m	2.4 m/km	52 m	-3 m	9.1%	Unavailable	2026-07-06
27	DRC's The Half (Dallas Running Club) Half Marathon - texas	0.1%	92 m	4.4 m/km	108 m	-16 m	13.3%	Unavailable	2026-07-06
28	ATW Bedford 10k & Half Marathon - east-of-england	0.1%	15 m	0.7 m/km	15 m	0 m	2.9%	Unavailable	2026-07-13
29	Novant Health Wilmington Marathon Half Marathon - north-carolina	0.1%	46 m	2.2 m/km	47 m	-0 m	4.6%	Unavailable	2026-07-06
30	Mississippi River Marathon Half Marathon - mississippi	0.1%	36 m	1.7 m/km	36 m	0 m	6.1%	Unavailable	2026-07-06
31	NLB Ljubljana Marathon Half Marathon - slovenia	0.1%	53 m	2.5 m/km	52 m	0 m	3.9%	Unavailable	2026-07-06
32	Mizuno Swansea Half Marathon - wales	0.1%	44 m	2.1 m/km	44 m	-0 m	5.6%	Unavailable	2026-07-24
33	Hartlepool Half Marathon - north-east	0.1%	50 m	2.4 m/km	52 m	-2 m	6.7%	Unavailable	2026-07-06
34	Martian Invasion of Races Half Marathon - michigan	0.1%	58 m	2.7 m/km	58 m	0 m	5.4%	Unavailable	2026-07-06
35	Toulouse Métropole Run Experience Half Marathon - france	0.1%	114 m	5.4 m/km	123 m	-10 m	11.2%	Unavailable	2026-07-06
36	Buffalo Stampede Half Marathon (Kearney) - nebraska	0.1%	75 m	3.6 m/km	78 m	-3 m	7.0%	Unavailable	2026-07-06
37	Bear Trail Half Marathon & 10K - delaware	0.2%	73 m	3.5 m/km	73 m	-0 m	4.9%	Unavailable	2026-07-06
38	Bay of Fundy International Marathon Half Marathon - maine	0.2%	176 m	8.3 m/km	203 m	-27 m	12.0%	Unavailable	2026-07-06
39	Bari Med Marathon Half Marathon - italy	0.2%	97 m	4.6 m/km	99 m	-3 m	6.3%	Unavailable	2026-07-06
40	Goodyear Half Marathon & 10K (Akron) - ohio	0.2%	109 m	5.2 m/km	119 m	-9 m	12.7%	Unavailable	2026-07-06
41	Parkway Subaru Battleship Half Marathon & GFL 10K\|5K (Wilmington) - north-carolina	0.2%	84 m	4.0 m/km	84 m	0 m	7.0%	Unavailable	2026-07-06
42	Cambridge Half Marathon - east-of-england	0.2%	95 m	4.5 m/km	95 m	-0 m	4.7%	Unavailable	2026-07-06
43	Maine Coast Marathon Half Marathon - maine	0.2%	68 m	3.2 m/km	67 m	1 m	8.0%	Unavailable	2026-07-23
44	Reims Champagne Run Half Marathon - france	0.2%	103 m	4.9 m/km	105 m	-2 m	4.9%	Unavailable	2026-07-06
45	Wilmslow Half Marathon - north-west	0.2%	111 m	5.2 m/km	114 m	-3 m	5.9%	Unavailable	2026-07-30
46	Belfast City Marathon Half Marathon - northern-ireland	0.2%	75 m	3.6 m/km	75 m	0 m	5.9%	£42	2026-07-06
47	Indiana Women's Running Festival (Indy Women's Half Marathon), Carmel - indiana	0.2%	86 m	4.1 m/km	85 m	0 m	5.4%	Unavailable	2026-07-06
48	Belfast City Half Marathon - northern-ireland	0.2%	88 m	4.2 m/km	89 m	-0 m	8.6%	£50	2026-07-06
49	University of Charleston Marathon (Charleston, WV) Half Marathon - west-virginia	0.2%	74 m	3.5 m/km	74 m	0 m	7.0%	Unavailable	2026-07-06
50	Regeneron Great Limerick Run Half Marathon - ireland	0.2%	114 m	5.4 m/km	117 m	-3 m	5.4%	Unavailable	2026-06-29
51	Mein Freiburg Marathon Half Marathon - germany	0.2%	105 m	5.0 m/km	104 m	1 m	6.2%	Unavailable	2026-07-06
52	Stormin' Norman Run Half Marathon - oklahoma	0.3%	94 m	4.4 m/km	94 m	-0 m	7.4%	Unavailable	2026-07-06
53	The Fury Run (Stormin' Norman Run), Norman Half Marathon - oklahoma	0.3%	94 m	4.4 m/km	94 m	-0 m	7.4%	Unavailable	2026-07-06
54	Debrecen Maraton Half Marathon - hungary	0.3%	94 m	4.5 m/km	94 m	0 m	5.6%	Unavailable	2026-07-06
55	Paavo Nurmi Marathon Half Marathon - finland	0.3%	91 m	4.3 m/km	92 m	-1 m	9.1%	Unavailable	2026-07-06
56	Stuttgart-Lauf Half Marathon - germany	0.3%	100 m	4.7 m/km	100 m	-1 m	9.8%	Unavailable	2026-07-06
57	Nagyerdei Terep Maraton (Debrecen) Half Marathon - hungary	0.3%	72 m	3.4 m/km	69 m	3 m	9.9%	Unavailable	2026-07-25
58	Maratona di Pisa Half Marathon - italy	0.3%	72 m	3.4 m/km	67 m	4 m	5.6%	Unavailable	2026-07-06
59	Albany COMBOS Marathon & Half Marathon - georgia	0.3%	154 m	7.3 m/km	160 m	-7 m	5.7%	Unavailable	2026-06-29
60	Garmin New Forest Marathon Half Marathon - south-east	0.3%	122 m	5.8 m/km	122 m	0 m	5.1%	£54	2026-06-26
61	David Cliff Wokingham Half Marathon - south-east	0.3%	117 m	5.6 m/km	117 m	-0 m	5.8%	£43	2026-06-26
62	Mercy Health Glass City Marathon Half Marathon - ohio	0.3%	92 m	4.4 m/km	88 m	4 m	6.2%	Unavailable	2026-07-06
63	Run Leicester Half Marathon - east-midlands	0.3%	114 m	5.4 m/km	114 m	-0 m	7.9%	£33	2026-06-29
64	Sioux Falls Skedaddle Half Marathon - south-dakota	0.3%	133 m	6.3 m/km	140 m	-7 m	13.3%	Unavailable	2026-06-29
65	Marathon des Alpes-Maritimes Nice-Cannes Half Marathon - france	0.4%	119 m	5.9 m/km	121 m	-2 m	11.7%	Unavailable	2026-07-23
66	ZeroWind Romeo&Giulietta Run Half Marathon (Verona) - italy	0.4%	55 m	2.6 m/km	42 m	12 m	7.3%	Unavailable	2026-07-06
67	SwissCityMarathon – Lucerne Half Marathon - switzerland	0.4%	103 m	4.9 m/km	104 m	-2 m	7.9%	Unavailable	2026-06-29
68	Cleveland Marathon Half Marathon - ohio	0.4%	102 m	4.8 m/km	102 m	-0 m	11.9%	Unavailable	2026-07-06
69	Regensburg Marathon Half Marathon - germany	0.4%	116 m	5.5 m/km	116 m	0 m	9.5%	Unavailable	2026-06-29
70	Wallis Sands Half Marathon - new-hampshire	0.4%	128 m	6.1 m/km	129 m	0 m	12.8%	Unavailable	2026-07-30
71	YMCA Harrisburg Marathon, Half, and Relay Presented by Enders Insurance Half Marathon - pennsylvania	0.4%	112 m	5.3 m/km	113 m	-0 m	11.1%	Unavailable	2026-06-29
72	Trondheim Maraton Half Marathon - norway	0.4%	127 m	6.0 m/km	125 m	1 m	8.3%	Unavailable	2026-06-29
73	Amica Newport Marathon & Half Marathon - rhode-island	0.4%	119 m	5.7 m/km	119 m	0 m	8.1%	Unavailable	2026-07-13
74	Haspa Marathon Hamburg Half Marathon - germany	0.5%	76 m	3.6 m/km	66 m	11 m	7.2%	Unavailable	2026-07-06
75	Colchester Half Marathon - east-of-england	0.5%	114 m	5.4 m/km	114 m	0 m	9.5%	£37	2026-06-27
76	Endurancelife Suffolk (Dunwich) Half Marathon - east-of-england	0.5%	123 m	5.7 m/km	124 m	0 m	11.0%	£47	2026-07-18
77	MountainOne Steel Rail Races (Adams) Half Marathon - massachusetts	0.5%	114 m	5.4 m/km	114 m	-0 m	10.6%	Unavailable	2026-07-06
78	Cajun Country Run Half Marathon - louisiana	0.5%	147 m	7.0 m/km	147 m	0 m	9.5%	Unavailable	2026-06-29
79	Göteborgsvarvet Half Marathon - sweden	0.5%	131 m	6.2 m/km	133 m	-2 m	7.6%	Unavailable	2026-06-26
80	Büchl Éjszakai Félmaraton (Győr) Half Marathon - hungary	0.5%	144 m	6.8 m/km	143 m	1 m	7.2%	Unavailable	2026-06-28
81	Michelob Ultra El Paso Marathon Half Marathon - texas	0.5%	151 m	7.2 m/km	150 m	1 m	9.4%	Unavailable	2026-06-29
82	Vienna City Marathon Half Marathon - austria	0.5%	71 m	3.4 m/km	58 m	13 m	8.2%	Unavailable	2026-07-06
83	Sioux Falls Marathon Half Marathon - south-dakota	0.5%	149 m	7.1 m/km	151 m	-2 m	8.0%	Unavailable	2026-06-29
84	DNB Oslo Marathon Half Marathon - norway	0.5%	153 m	7.2 m/km	153 m	-0 m	6.5%	Unavailable	2026-06-26
85	City of Colleges Half Marathon - arkansas	0.5%	134 m	6.3 m/km	135 m	-0 m	9.2%	Unavailable	2026-06-29
86	Thames Meander Marathon (London) Half Marathon - london	0.5%	159 m	7.6 m/km	159 m	0 m	6.5%	Unavailable	2026-07-29
87	Helsinki City Marathon Half Marathon - finland	0.5%	122 m	5.8 m/km	117 m	6 m	7.1%	Unavailable	2026-06-25
88	Milton Keynes Marathon Half Marathon - south-east	0.5%	162 m	7.7 m/km	165 m	-3 m	8.1%	Unavailable	2026-06-27
89	Omaha Marathon Half Marathon - nebraska	0.5%	150 m	7.1 m/km	151 m	-1 m	11.5%	Unavailable	2026-06-29
90	The Original Las Vegas Marathon Half Marathon - nevada	0.6%	164 m	7.8 m/km	164 m	0 m	11.9%	Unavailable	2026-07-29
91	Madison Marathon (Madison, Wisconsin) Half Marathon - wisconsin	0.6%	112 m	5.3 m/km	106 m	6 m	8.7%	Unavailable	2026-06-29
92	Maine Marathon (Portland) Half Marathon - maine	0.6%	133 m	6.3 m/km	133 m	0 m	9.8%	Unavailable	2026-07-23
93	Wisconsin Lakeside Half Marathon & 5K (Monona) - wisconsin	0.6%	126 m	6.0 m/km	127 m	-0 m	14.6%	Unavailable	2026-06-29
94	Rimi Riga Marathon Half Marathon - latvia	0.6%	135 m	6.4 m/km	134 m	1 m	18.7%	Unavailable	2026-07-29
95	PeaceHealth Appletree Marathon Half Marathon - washington	0.6%	147 m	7.0 m/km	147 m	1 m	8.0%	Unavailable	2026-06-29
96	Weymouth Half Marathon - south-west	0.6%	146 m	6.9 m/km	146 m	-1 m	9.2%	£41	2026-06-27
97	Charlotte Racefest at SouthPark Half Marathon and 10K - north-carolina	0.6%	70 m	3.3 m/km	59 m	11 m	15.6%	Unavailable	2026-07-06
98	Phoenix 10k & Half Marathon - arizona	0.6%	169 m	8.0 m/km	169 m	0 m	7.3%	Unavailable	2026-06-29
99	OhioHealth Capital City Half & Quarter Marathon (Columbus) Half Marathon - ohio	0.6%	142 m	6.7 m/km	142 m	0 m	14.9%	Unavailable	2026-06-29
100	Midnattssolmaraton (Midnight Sun Marathon), Tromsø Half Marathon - norway	0.7%	148 m	7.0 m/km	147 m	2 m	7.5%	Unavailable	2026-07-24

Showing the top 100 of 191 qualifying races; use the distance catalogue for the full searchable list. Scores are out of 100 when present; route, elevation and cost figures are shown in their natural units.

How we ranked these

Races are ranked by GAP factor. Score metrics use methodology scoring-methodology-v1.0. Elevation rankings use only trusted raw-elevation course profiles. A ranking is only published when at least five races qualify, so the table is never padded with thin data.

See exactly how each figure is calculated →

Route maps for this ranking

Verified route-map ranking
Open the sibling route-map ranking built only from races with stored route geometry and the required route metric.

How we calculated this

Published facts and derived model outputs on this page are tied to stored sources or a published, version-locked methodology. We show the provenance so runners, coaches and organisers can check it. Data on this page is current as of 2026-07-30.

Derived numbers use scoring-methodology-v1.0.

Sources used on this page (193)

Layer A visiteastbourne.com · last check inconclusive on 2026-07-14
Layer A cambridgehalfmarathon.com · last check inconclusive on 2026-07-15
Layer A runmadtown.com · last check inconclusive on 2026-07-29
Layer A southamptonmarathon.co.uk · last check inconclusive on 2026-07-29
Layer A swanseahalfmarathon.co.uk · verified 2026-07-24
Layer E archive-api.open-meteo.com
Layer A runleicester.co.uk · verified 2026-07-29
Layer A activeleisureevents.co.uk · source unreachable when last checked on 2026-07-16
Layer A relishrunningraces.com · last check inconclusive on 2026-07-29
Layer A oslomaraton.no · last check inconclusive on 2026-07-17
Layer A generaligenevemarathon.com · last check inconclusive on 2026-07-19
Layer A haspa-marathon-hamburg.de · last check inconclusive on 2026-07-20
Layer A zuerichmarathon.ch · last check inconclusive on 2026-07-30
Layer A wilmingtonncmarathon.com · verified 2026-07-25
Layer A theoriginallasvegasmarathon.org · verified 2026-07-29
Layer A mainecoastmarathon.com · verified 2026-07-23
Layer A epmarathon.org · verified 2026-07-18
Layer A newportmarathon.com · verified 2026-07-13
Layer B src_derived
Layer A msbluesmarathon.events · last check inconclusive on 2026-07-24
Layer A blueridgemarathon.com · last check inconclusive on 2026-07-19
Layer A capitalcityhalfmarathon.com · fetched 2026-06-22 · last check inconclusive on 2026-07-26
Layer A theraceuc.com · last check inconclusive on 2026-07-29
Layer A runsignup.com · last check inconclusive on 2026-07-20
Layer A madisonmarathon.org · source blocked automated checking on 2026-07-23
Layer A martianraces.com · fetched 2026-06-24 · source unreachable when last checked on 2026-07-23
Layer A womensrunningfestival.com · last check inconclusive on 2026-07-21
Layer A runsignup.com · last check inconclusive on 2026-07-22
Layer A omahamarathon.com · last check inconclusive on 2026-07-26
Layer A flyingpigmarathon.com · last check inconclusive on 2026-07-27
Layer A vienna-marathon.com · source has moved; last reachable 2026-07-30
Layer A wildduluthraces.com · last check inconclusive on 2026-07-29
Layer A runmadcity.com · last check inconclusive on 2026-07-29
Layer A runstillwater.com · last check inconclusive on 2026-07-29
Layer A ashevillemarathon.com · last check inconclusive on 2026-07-30
Layer A elpasomarathon.org · source unreachable when last checked on 2026-07-24
Layer A brazenracing.com · last check inconclusive on 2026-07-29
Layer A storminnormanrun.com · last check inconclusive on 2026-07-30
Layer A thewoodlandsmarathon.com · last check inconclusive on 2026-07-30
Layer A bigrivertrailseries.com · fetched 2026-06-24 · verified 2026-07-30
Layer A ascentruns.com · fetched 2026-06-24 · last check inconclusive on 2026-07-15
Layer A steependurance.com · last check inconclusive on 2026-07-24
Layer A steelrailraces.com · fetched 2026-06-24 · source unreachable when last checked on 2026-07-24
Layer A silverstatestriders.com · verified 2026-07-29
Layer A runsignup.com · last check inconclusive on 2026-07-15
Layer A kearneyymca.org · last check inconclusive on 2026-07-15
Layer A cityofcollegeshalf.com · last check inconclusive on 2026-07-16
Layer A mainemarathon.com · verified 2026-07-23
Layer A rivalraceseries.com · source has moved; last reachable 2026-07-14
Layer A bozemanmarathon.com · last check inconclusive on 2026-07-15
Layer A runsignup.com · last check inconclusive on 2026-07-21
Layer A belfastcitymarathon.com · last check inconclusive on 2026-07-14
Layer A cheltenhamrunningfestival.com · last check inconclusive on 2026-07-16
Layer A endurancelife.com · verified 2026-07-18
Layer A newforestmarathon.co.uk · last check inconclusive on 2026-07-19
Layer A bustinskintriathlonclub.clubtrac.co.uk · last check inconclusive on 2026-07-27
Layer A 1m2go.co.uk · source unreachable when last checked on 2026-07-27
Layer A justracinguk.com · source blocked automated checking on 2026-07-30
Layer A threefortschallenge.org.uk · fetched 2026-06-24 · last check inconclusive on 2026-07-30
Layer A dolomitiextremetrail.com · fetched 2026-06-24 · source unreachable when last checked on 2026-07-17
Layer A runclon.ie · fetched 2026-06-24 · last check inconclusive on 2026-07-16
Layer A bolognamarathon.run · fetched 2026-06-24 · last check inconclusive on 2026-07-30
Layer A dolomitidibrentatrail.it · fetched 2026-06-24 · last check inconclusive on 2026-07-17
Layer A xn--tirol-luft-w5a.com · last check inconclusive on 2026-07-30
Layer A swisscitymarathon.ch · last check inconclusive on 2026-07-30
Layer A chudywawrzyniec.pl · last check inconclusive on 2026-07-16
Layer A cretehm.com · last check inconclusive on 2026-07-17
Layer A debrecenmaraton.hu · last check inconclusive on 2026-07-17
Layer A maratonadicatania.it · last check inconclusive on 2026-07-25
Layer A mediamaratonsantander.com · last check inconclusive on 2026-07-24
Layer A montpellierrunfestival.fr · last check inconclusive on 2026-07-24
Layer A dallasrunningclub.com · last check inconclusive on 2026-07-17
Layer A maratonadipisa.com · last check inconclusive on 2026-07-23
Layer A ultratrail.hu · last check inconclusive on 2026-07-29
Layer A stavangermarathon.no · last check inconclusive on 2026-07-29
Layer A trondheimmaraton.no · last check inconclusive on 2026-07-29
Layer A trondheimskogsmaraton.no · source unreachable when last checked on 2026-07-29
Layer A reimschampagnerun.fr · last check inconclusive on 2026-07-27
Layer A tatraskymarathon.pl · last check inconclusive on 2026-07-30
Layer A telekomvivicitta.hu · last check inconclusive on 2026-07-30
Layer A 3sjoers.no · verified 2026-07-12
Layer A 6sjoar.se · fetched 2026-06-24 · verified 2026-07-12
Layer A visitalbanyga.com · last check inconclusive on 2026-07-13
Layer A aletsch-halbmarathon.ch · fetched 2026-06-24 · last check inconclusive on 2026-07-13
Layer A richmondmarathon.org · last check inconclusive on 2026-07-13
Layer A wildmarathon.com · verified 2026-07-13
Layer A vailrec.com · last check inconclusive on 2026-07-13
Layer A atwevents.co.uk · verified 2026-07-13
Layer A barimedmarathon.it · last check inconclusive on 2026-07-13
Layer A relishrunningraces.com · last check inconclusive on 2026-07-14
Layer A bayoffundymarathon.com · last check inconclusive on 2026-07-14
Layer A belfastcitymarathon.com · fetched 2026-06-21 · last check inconclusive on 2026-07-14
Layer A bend-marathon.com · fetched 2026-06-22 · last check inconclusive on 2026-07-14
Layer A bostonsruntoremember.org · fetched 2026-06-24 · last check inconclusive on 2026-07-15
Layer A gyorisport.hu · last check inconclusive on 2026-07-15
Layer A cajuncountry.run · last check inconclusive on 2026-07-15
Layer A cedarrapidsmarathon.com · last check inconclusive on 2026-07-16
Layer A charlotteracefest.raceroster.com · last check inconclusive on 2026-07-16
Layer A clevelandmarathon.com · last check inconclusive on 2026-07-16
Layer A colchesterhalfmarathon.com · last check inconclusive on 2026-07-16
Layer A columbiagorgemarathon.com · fetched 2026-06-22 · last check inconclusive on 2026-07-16
Layer A connemarathon.com · fetched 2026-06-24 · last check inconclusive on 2026-07-16
Layer A coursesdestrasbourg.eu · last check inconclusive on 2026-07-16
Layer A wokinghamhalfmarathon.com · last check inconclusive on 2026-07-17
Layer A endurancelife.com · last check inconclusive on 2026-07-18
Layer A endurancelife.com · fetched 2026-06-24 · last check inconclusive on 2026-07-18
Layer A tahoemtnmilers.org · fetched 2026-06-24 · verified 2026-07-18
Layer A fayettevillehalfmarathon.com · last check inconclusive on 2026-07-18
Layer A akronmarathon.org · fetched 2026-06-22 · last check inconclusive on 2026-07-18
Layer A bergencitymarathon.no · last check inconclusive on 2026-07-18
Layer A flyingpigmarathon.com · last check inconclusive on 2026-07-18
Layer A utemountaineer.com · last check inconclusive on 2026-07-19
Layer A akronmarathon.org · last check inconclusive on 2026-07-19
Layer A zermattmarathon.ch · fetched 2026-06-24 · last check inconclusive on 2026-07-19
Layer A goteborgsvarvet.se · fetched 2026-06-24 · last check inconclusive on 2026-07-19
Layer A en.wikipedia.org · last check inconclusive on 2026-07-20
Layer A vacationraces.com · last check inconclusive on 2026-07-20
Layer A greifenseelauf.ch · fetched 2026-06-24 · last check inconclusive on 2026-07-20
Layer A activehartlepool.co.uk · last check inconclusive on 2026-07-20
Layer A bendraces.com · last check inconclusive on 2026-07-20
Layer A helsinkicityrun.fi · last check inconclusive on 2026-07-20
Layer A runwithpaula.com · last check inconclusive on 2026-07-20
Layer A princetonhalfmarathon.com · last check inconclusive on 2026-07-20
Layer A ocmarathon.com · last check inconclusive on 2026-07-20
Layer A hoodoobrew.com · last check inconclusive on 2026-07-20
Layer A downhilltodowntown.com · last check inconclusive on 2026-07-29
Layer A porto-half-marathon.com · fetched 2026-06-24 · last check inconclusive on 2026-07-21
Layer A iceagetrail50.com · last check inconclusive on 2026-07-21
Layer A idahofallsmarathon.com · last check inconclusive on 2026-07-21
Layer A skyehalfmarathon.com · last check inconclusive on 2026-07-21
Layer A jackjillmarathon.com · last check inconclusive on 2026-07-21
Layer A mdiymca.org · verified 2026-07-12
Layer A cvrunners.org · verified 2026-07-12
Layer A stalbanshalfmarathon.com · last check inconclusive on 2026-07-29
Layer A lajollahalfmarathon.com · last check inconclusive on 2026-07-22
Layer A lakelandtrails.org · last check inconclusive on 2026-07-22
Layer A runstillwater.com · fetched 2026-06-24 · last check inconclusive on 2026-07-22
Layer A sportingeventsuk.com · last check inconclusive on 2026-07-23
Layer A marathon06.com · verified 2026-07-23
Layer A marshalluniversitymarathon.com · last check inconclusive on 2026-07-23
Layer A mauioceanfrontmarathon.com · verified 2026-07-23
Layer A umc.edu · last check inconclusive on 2026-07-29
Layer A runwoodstock.com · last check inconclusive on 2026-07-29
Layer A mein-freiburgmarathon.de · last check inconclusive on 2026-07-24
Layer A glasscitymarathon.org · last check inconclusive on 2026-07-24
Layer A middleburymaplerun.com · last check inconclusive on 2026-07-24
Layer A msm.no · verified 2026-07-24
Layer A madisonminimarathon.com · source page changed since our last check on 2026-07-24
Layer A mkmarathon.com · last check inconclusive on 2026-07-24
Layer A msrivermarathon.raceroster.com · last check inconclusive on 2026-07-24
Layer A 406raceseries.com · last check inconclusive on 2026-07-24
Layer A runmdi.org · last check inconclusive on 2026-07-24
Layer A vacationraces.com · verified 2026-07-25
Layer A nagyerdeimaraton.hu · verified 2026-07-25
Layer A naptownrun.com · last check inconclusive on 2026-07-25
Layer A ljubljanskimaraton.si · last check inconclusive on 2026-07-25
Layer A zigzagrunning.co.uk · last check inconclusive on 2026-07-25
Layer A runsignup.com · fetched 2026-06-24 · last check inconclusive on 2026-07-26
Layer A juoksuaika.fi · last check inconclusive on 2026-07-26
Layer A battleshiphalfmarathon.com · last check inconclusive on 2026-07-26
Layer A whyracingevents.com · last check inconclusive on 2026-07-26
Layer A phoenix10k.com · last check inconclusive on 2026-07-26
Layer A np-plitvicka-jezera.hr · last check inconclusive on 2026-07-26
Layer A idaph.net · last check inconclusive on 2026-07-27
Layer A greatlimerickrun.com · fetched 2026-06-24 · last check inconclusive on 2026-07-27
Layer A regensburg-marathon.de · last check inconclusive on 2026-07-27
Layer A rimirigamarathon.com · verified 2026-07-29
Layer A flowercitychallenge.com · last check inconclusive on 2026-07-29
Layer A siouxfallsmarathon.com · last check inconclusive on 2026-07-29
Layer A runsignup.com · fetched 2026-06-24 · last check inconclusive on 2026-07-29
Layer A wallissandshalfmarathon.com · verified 2026-07-30
Layer A thekauaimarathon.com · last check inconclusive on 2026-07-29
Layer A evensplits.events · last check inconclusive on 2026-07-29
Layer A sparkassen-phoenix-halbmarathon.de · last check inconclusive on 2026-07-29
Layer A dinoseries.com · last check inconclusive on 2026-07-29
Layer A hermesrunning.com · verified 2026-07-29
Layer A uwnorthidaho.org · last check inconclusive on 2026-07-29
Layer A stuttgart-lauf.de · last check inconclusive on 2026-07-30
Layer A trailanimals.com · last check inconclusive on 2026-07-30
Layer A thefuryrun.com · last check inconclusive on 2026-07-30
Layer A wilmslowrunningfestival.org.uk · verified 2026-07-30
Layer A nsplit.com · fetched 2026-06-22 · last check inconclusive on 2026-07-30
Layer A nebraskamarathon.org · last check inconclusive on 2026-07-30
Layer A tobaccoroadmarathon.com · last check inconclusive on 2026-07-30
Layer A 26extreme.com · last check inconclusive on 2026-07-30
Layer A harmonie-mutuelle.toulouserunexperience.fr · last check inconclusive on 2026-07-30
Layer A triestespringrun.com · last check inconclusive on 2026-07-30
Layer A rhodesmarathon.gr · last check inconclusive on 2026-07-30
Layer A ucwv.edu · last check inconclusive on 2026-07-30
Layer A hbgyrun.org · last check inconclusive on 2026-07-30
Layer A zagorirace.gr · last check inconclusive on 2026-07-30
Layer A romeoegiuliettarunhalfmarathon.it · last check inconclusive on 2026-07-30
Layer A rocknrollmadridrun.com · fetched 2026-06-21 · last check inconclusive on 2026-07-30

Read the full methodology →

Common questions

What is the lowest gap factor half marathons?

Estes Park Marathon and Half Marathon ranks first by gap factor, from 191 qualifying races compared under our published methodology.

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Which race ranks first — and why is it Estes Park Marathon and Half Marathon?

How we ranked these

Route maps for this ranking

Verified route-map ranking

How we calculated this

Common questions

What is the lowest gap factor half marathons?

Which race ranks first — and why is it Estes Park Marathon and Half Marathon?

How we ranked these

Route maps for this ranking

Verified route-map ranking

How we calculated this

Common questions

What is the lowest gap factor half marathons?