The closest flags in the world

All 254 of them, ranked by how close the nearest other flag in the world is. The number is measured off the pictures, not off anybody's opinion of them: two copies of one picture score 0.

The closest flags in the worldEvery flag measured against every other. 0 is the same picture.

1
Chad vs Romania10.7
2
El Salvador vs Nicaragua23.5
3
Egypt vs Yemen25.3
4
Caribbean Netherlands vs Paraguay27.4
5
Netherlands vs Paraguay27.4
6
British Virgin Islands vs Cayman Islands28.2
7
Hungary vs Tajikistan32.8
8
Montenegro vs Vietnam32.9
9
Kyrgyzstan vs Montenegro33.6
10
Honduras vs Nicaragua34

flagory.com/closest

All 254, in order

Each flag with the one measured nearest to it, and how far apart they are. Take the table as a CSV.

#	Flag	Nearest to it	Apart
1	Chad	Romania	10.7
2	Romania	Chad	10.7
3	El Salvador	Nicaragua	23.5
4	Nicaragua	El Salvador	23.5
5	Egypt	Yemen	25.3
6	Yemen	Egypt	25.3
7	Caribbean Netherlands	Paraguay	27.4
8	Netherlands	Paraguay	27.4
9	Paraguay	Caribbean Netherlands	27.4
10	British Virgin Islands	Cayman Islands	28.2
11	Cayman Islands	British Virgin Islands	28.2
12	Hungary	Tajikistan	32.8
13	Tajikistan	Hungary	32.8
14	Montenegro	Vietnam	32.9
15	Vietnam	Montenegro	32.9
16	Kyrgyzstan	Montenegro	33.6
17	Honduras	Nicaragua	34
18	Palestine	Western Sahara	34.6
19	Western Sahara	Palestine	34.6
20	Somalia	United Nations	35.7
21	United Nations	Somalia	35.7
22	Pitcairn Islands	British Virgin Islands	36.7
23	Mali	Senegal	37.3
24	Senegal	Mali	37.3
25	Iraq	Egypt	37.5
26	Hong Kong	Tunisia	38.7
27	Saint Helena, Ascension and Tristan da Cunha	Turks and Caicos Islands	38.7
28	Tunisia	Hong Kong	38.7
29	Turks and Caicos Islands	Saint Helena, Ascension and Tristan da Cunha	38.7
30	Indonesia	Monaco	39.2
31	Monaco	Indonesia	39.2
32	France	Italy	40.7
33	French Guiana	Italy	40.7
34	Guadeloupe	Italy	40.7
35	Italy	Saint Barthélemy	40.7
36	Mayotte	Italy	40.7
37	Micronesia	Somalia	40.7
38	New Caledonia	Italy	40.7
39	Réunion	Italy	40.7
40	Saint Barthélemy	Italy	40.7
41	Saint Martin	Italy	40.7
42	Saint Pierre and Miquelon	Italy	40.7
43	Wallis and Futuna	Italy	40.7
44	England	Guernsey	40.9
45	Guernsey	England	40.9
46	South Georgia	British Virgin Islands	41.8
47	Cook Islands	New Zealand	42.1
48	New Zealand	Cook Islands	42.1
49	Bahrain	Qatar	42.9
50	Qatar	Bahrain	42.9
51	British Indian Ocean Territory	Fiji	44.7
52	Fiji	British Indian Ocean Territory	44.7
53	Belgium	Chad	46.1
54	Andorra	Moldova	49.4
55	Moldova	Andorra	49.4
56	Falkland Islands	Montserrat	49.6
57	Montserrat	Falkland Islands	49.6
58	Bulgaria	Russia	49.7
59	Ireland	Italy	49.7
60	Russia	Bulgaria	49.7
61	China	North Macedonia	50.6
62	North Macedonia	China	50.6
63	Lithuania	Venezuela	52
64	Venezuela	Lithuania	52
65	Kenya	Malawi	53.7
66	Malawi	Kenya	53.7
67	Luxembourg	Paraguay	54.4
68	India	Egypt	55.3
69	Isle of Man	North Macedonia	56
70	Anguilla	Falkland Islands	59
71	Türkiye	North Macedonia	59.3
72	Iceland	Sweden	59.6
73	Sweden	Iceland	59.6
74	European Union	Guam	60.3
75	Guam	European Union	60.3
76	Faroe Islands	Finland	61.1
77	Finland	Faroe Islands	61.1
78	Bolivia	Ghana	61.2
79	Ghana	Bolivia	61.2
80	Angola	Morocco	62.4
81	Morocco	Angola	62.4
82	Belize	Laos	63.1
83	Laos	Belize	63.1
84	Nauru	Kenya	63.6
85	Croatia	Paraguay	63.8
86	Tuvalu	British Indian Ocean Territory	64.6
87	Argentina	Israel	65.1
88	Israel	Argentina	65.1
89	Gambia	Latvia	65.7
90	Latvia	Gambia	65.7
91	Australia	Cook Islands	66.4
92	Heard Island and McDonald Islands	Cook Islands	66.4
93	Åland Islands	Sweden	66.7
94	Macau	Somalia	66.7
95	Singapore	Monaco	67.7
96	Curaçao	Saudi Arabia	67.8
97	Saudi Arabia	Curaçao	67.8
98	French Polynesia	Lebanon	68.9
99	Lebanon	French Polynesia	68.9
100	Mexico	Senegal	69
101	Austria	Latvia	69.4
102	Sri Lanka	Morocco	69.4
103	Cameroon	Portugal	70
104	Portugal	Cameroon	70
105	Spain	China	70
106	Dominica	Sweden	70.4
107	Azerbaijan	Gabon	71
108	Gabon	Azerbaijan	71
109	Georgia	England	72
110	Cocos (Keeling) Islands	Morocco	72.3
111	Northern Mariana Islands	United Nations	72.3
112	Libya	Vanuatu	72.8
113	Vanuatu	Libya	72.8
114	Guatemala	Nigeria	73
115	Nigeria	Guatemala	73
116	Slovenia	Russia	73.1
117	Turkmenistan	Saudi Arabia	73.7
118	Switzerland	Tunisia	74
119	Armenia	Lithuania	74.3
120	Syria	Honduras	75
121	Niger	India	75.1
122	Burkina Faso	Angola	75.6
123	Benin	Portugal	75.7
124	Albania	Morocco	76.2
125	Uzbekistan	Nicaragua	76.3
126	Aruba	Micronesia	77
127	Brazil	Dominica	77
128	Sierra Leone	Honduras	78
129	Costa Rica	Suriname	78.3
130	Suriname	Costa Rica	78.3
131	Denmark	North Macedonia	78.7
132	Thailand	Suriname	78.7
133	Botswana	Aruba	79
134	Afghanistan	United States Virgin Islands	80.5
135	United States Virgin Islands	Afghanistan	80.5
136	Scotland	Micronesia	81.2
137	Bouvet Island	Latvia	81.3
138	Cape Verde	Iceland	81.3
139	Norway	Latvia	81.3
140	Svalbard and Jan Mayen	Latvia	81.3
141	Bangladesh	Sweden	81.6
142	Bermuda	Liberia	82.1
143	Liberia	Bermuda	82.1
144	Solomon Islands	Saudi Arabia	82.5
145	Antarctica	Micronesia	82.6
146	Eritrea	Guyana	82.8
147	Guyana	Eritrea	82.8
148	San Marino	Micronesia	83
149	Trinidad and Tobago	Morocco	83
150	Samoa	United States Minor Outlying Islands	83.3
151	United States	Samoa	83.3
152	United States Minor Outlying Islands	Samoa	83.3
153	Saint Lucia	Afghanistan	83.7
154	Maldives	Guam	83.8
155	Cambodia	Gabon	84.5
156	Madagascar	Qatar	84.7
157	Colombia	Ecuador	85.1
158	Ecuador	Colombia	85.1
159	DR Congo	Namibia	85.4
160	Namibia	DR Congo	85.4
161	Kazakhstan	Somalia	85.5
162	Greece	Micronesia	85.8
163	Papua New Guinea	Angola	86
164	Germany	Albania	86.4
165	Niue	North Macedonia	88
166	Norfolk Island	Saint Vincent and the Grenadines	88
167	Saint Vincent and the Grenadines	Norfolk Island	88
168	Christmas Island	Saudi Arabia	88.7
169	Timor-Leste	Isle of Man	88.8
170	Mauritius	Malawi	89
171	Peru	Belgium	89.3
172	Grenada	Liberia	89.6
173	Iran	Latvia	89.7
174	Kiribati	Sri Lanka	89.7
175	Martinique	Cocos (Keeling) Islands	89.7
176	Japan	San Marino	89.8
177	North Korea	Suriname	89.8
178	Togo	Suriname	90.2
179	Barbados	Norfolk Island	90.7
180	Cyprus	United States Virgin Islands	91.7
181	Mauritania	Belize	92
182	Guinea-Bissau	Angola	92.4
183	São Tomé and Príncipe	Sri Lanka	92.4
184	Tanzania	Namibia	92.4
185	Eswatini	Suriname	92.9
186	Ethiopia	Latvia	92.9
187	French Southern and Antarctic Lands	Australia	93
188	Liechtenstein	Morocco	93
189	Belarus	Morocco	93.7
190	Chile	Liberia	93.9
191	Guinea	Ivory Coast	94
192	Ivory Coast	Guinea	94
193	Uganda	Kyrgyzstan	94
194	United Kingdom	Åland Islands	94.6
195	Jamaica	Turkmenistan	94.8
196	Mozambique	Germany	95.2
197	Dominican Republic	Latvia	95.3
198	Taiwan	Samoa	95.4
199	Uruguay	United States Virgin Islands	95.4
200	South Korea	Afghanistan	95.5
201	Bahamas	Cambodia	95.7
202	Malaysia	Morocco	95.7
203	South Sudan	Nauru	95.7
204	Tokelau	Samoa	96
205	Jersey	Israel	96.1
206	Zambia	Solomon Islands	96.4
207	Serbia	Liberia	96.9
208	Haiti	Belize	97
209	Lesotho	El Salvador	97.3
210	Myanmar	North Macedonia	98
211	Mongolia	Liberia	98.2
212	United Arab Emirates	Latvia	98.3
213	Jordan	Latvia	98.7
214	Palau	Bangladesh	98.8
215	Ukraine	Liberia	98.8
216	Bhutan	Myanmar	99.4
217	Canada	Liberia	99.6
218	Marshall Islands	DR Congo	100.4
219	Antigua and Barbuda	Belize	100.8
220	Rwanda	Cape Verde	100.9
221	Saint Kitts and Nevis	Dominica	101.7
222	Sudan	Western Sahara	102.3
223	Slovakia	Bulgaria	102.7
224	Bosnia and Herzegovina	Morocco	103.3
225	South Africa	Turkmenistan	103.4
226	Estonia	Botswana	103.8
227	Vatican City	Cyprus	104.3
228	Djibouti	Micronesia	106.1
229	Republic of the Congo	Sri Lanka	106.1
230	Cuba	Liberia	106.2
231	Kuwait	United Arab Emirates	106.6
232	Poland	Colombia	107.7
233	Seychelles	Liberia	107.9
234	Burundi	North Macedonia	108.4
235	Central African Republic	Latvia	108.6
236	American Samoa	Somalia	110.1
237	Algeria	Liberia	110.6
238	Equatorial Guinea	Liberia	111.2
239	Sint Maarten	South Sudan	113.8
240	Oman	Lithuania	114.3
241	Philippines	British Indian Ocean Territory	115.1
242	Zimbabwe	British Indian Ocean Territory	116
243	Comoros	Spain	117.7
244	Pakistan	Aruba	119.5
245	Greenland	Bhutan	125.3
246	Tonga	Colombia	125.3
247	Wales	Colombia	126.3
248	Nepal	British Indian Ocean Territory	127.6
249	Puerto Rico	Liberia	128.9
250	Malta	Uruguay	129.6
251	Czechia	Comoros	131.7
252	Gibraltar	India	140.3
253	Panama	British Indian Ocean Territory	141.6
254	Brunei	Spain	145.2

How to get this number yourself

Every flag is drawn at 64×48 and cut into squares 8 across. Each square is averaged to one colour. Two flags are compared square against square, and the score is the worst single square — so two flags that agree everywhere except one corner are as far apart as that corner. 0 is the same picture; the number is the worst single tile, out of 255. This table is each flag's smallest such score against any flag not flying its own design.

All of it is in the open. The pictures are in the repository, the numbers are in content/similarity.json beside them, and npm run content:build writes that file from those pictures. Nothing was typed in, and nothing here needs to be taken on trust: npm run content:validate measures every pair again and refuses the file if it is not what came out.

What it cannot see. Every flag is stretched to the same box, so the shape of the flag and how wide it is flown are gone — two flags identical but for their proportions are not measured as identical, and two flags of very different shape are not pushed apart by it. A square is an eighth of the flag across, so a coat of arms, a star or a line of writing is averaged into the field behind it rather than counted. And it knows nothing about meaning: it compares pictures, and a person telling two flags apart has more than a picture to go on.