Here are the income tax rates (in % including regional surcharges) for the maximum tiered income slab for each country in ascending order of tax rate,
Anguilla 0%
Bahamas 0%
Bahrain 0%
Bermuda 0%
Brunei Darussalam 0%
Cayman Islands 0%
Kuwait 0%
Oman 0%
Qatar 0%
Saudi Arabia 0%
United Arab Emirates 0%
Guatemala 7%
Montenegro 9%
Bosnia and Herzegovina 10%
Bulgaria 10%
Kazakhstan 10%
Macedonia 10%
Mongolia 10%
Romania 10%
Serbia 10%
Paraguay 10%
Libya 10%
Macau 12%
Belarus 13%
Russia 13%
Bolivia 13%
Costa Rica 15%
Hong Kong SAR 15%
Hungary 15%
Iraq 15%
Lithuania 15%
Mauritius 15%
Sierra Leone 15%
Sudan 15%
Yemen 15%
Angola 17%
Moldova 18%
Ukraine 18%
Afghanistan 20%
Estonia 20%
Fiji 20%
Georgia 20%
Guernsey 20%
Isle of Man 20%
Jersey 20%
Jordan 20%
Lebanon 20%
Pakistan 20%
Madagascar 20%
Czech Republic 22%
Singapore 22%
Syria 22%
Egypt 22.5%
Albania 23%
Nigeria 24%
Sri Lanka 24%
Antigua and Barbuda 25%
Botswana 25%
Dominican Republic 25%
Ghana 25%
Honduras 25%
Myanmar 25%
Panama 25%
Slovakia 25%
Trinidad and Tobago 25%
Samoa 27%
Brazil 27.5%
Malaysia 28%
Bangladesh 30%
Congo 30%
El Salvador 30%
Indonesia 30%
Jamaica 30%
Kenya 30%
Malawi 30%
Nicaragua 30%
Peru 30%
Tanzania 30%
Guyana 30%
Latvia 31.4%
Mozambique 32%
Poland 32%
Canada 33%
New Zealand 33%
Puerto Rico 33%
Swaziland 33%
Barbados 33.5%
Venezuela 34%
Algeria 35%
Argentina 35%
Chile 35%
Colombia 35%
Cyprus 35%
Ecuador 35%
Ethiopia 35%
Malta 35%
Mexico 35%
Netherlands Antilles 35%
Philippines 35%
Thailand 35%
Tunisia 35%
Turkey 35%
Vietnam 35%
Niger 35%
India 35.88%
Armenia 36%
Croatia 36%
Uruguay 36%
Namibia 37%
United States 37%
Zambia 37.5%
Morocco 38%
Suriname 38%
Congo (Democratic Republic of the) 40%
Gibraltar 40%
Mauritania 40%
Senegal 40%
Switzerland 40%
Taiwan 40%
Uganda 40%
Mali 40%
Korea, Republic of 42%
Papua New Guinea 42%
Italy 43%
Greenland 44%
Australia 45%
China 45%
Germany 45%
Greece 45%
South Africa 45%
Spain 45%
United Kingdom 45%
Luxembourg 45.78%
Iceland 46.24%
Norway 46.6%
Curacao 47%
Ireland 48%
Portugal 48%
Sint Maarten (Dutch) 48%
St Maarten 48%
France 49%
Belgium 50%
Israel 50%
Slovenia 50%
Zimbabwe 51.5%
Netherlands 51.95%
Finland 53.75%
Austria 55%
Denmark 55.85%
Japan 55.95%
Sweden 57.34%
Aruba 59%
Chad 60%
Ivory Coast 60%