There is of course the IATA visa tool, but there you need to enter country + personal details to get visa details.
If I want to know my options, it can become quite a nuisance to get a full list. Is there an easier way to know the countries I am eligible to enter visa-free?
Wikipedia's list of Visa requirements for X citizens articles is surprisingly comprehensive and up to date. It's not perfect or complete, and it's definitely better for nationalities that are heavily represented among the editorship, but if you happen to come from any large-ish English-speaking country you're gold. Obviously you'll want to double-check any specific claims on Timatic etc before you go ahead and book your flights!
The best lists I know of are on Wikipedia, they cover more subtleties than just "visa-free" but they are unfortunately not 100% complete probably because 300 some citizenships multiples by 300 some countries to visit would result in 90,000 entries to get right and maintain.
Sometimes you don't need a visa at all, sometimes you don't need a visa but you need something else (eta for Australia, esta for USA). Sometimes these are very restricted, such as one or two days and only if you enter at certain airports.
For instance I'm an Australian citizen with only an Australian passport so I can consult this Wikipedia article:
From your Stack Exchange profile I'm going to assume that you travel on a Belgian passport so your Wikipedia article is:
Though it's not complete it's a wiki so when you go to the trouble to find out some information for your needs that's not yet included, you can edit the article and add the information as a way to thank Wikipedia and help everybody else that looks there when they're in a similar situation to yours.
