[Technically] you are supposed to be able to show at least the equivalent of 20,000 (Single, 40,000 Couple/Family) in CASH when you enter Thailand Visa Exempt - This can be in any Currency & given the poor exchange rate you will get for SEK it might be worth buying USD in Sweden to be able to show this & to exchange when here. It was almost unheard of for them to ask to see this unless they were looking to deny you entry (most commonly because you had done too many Visa Exempt visits) but the "Rules" are they can ask you for this alongside proof of onward travel & hotel bookings. Sounds like it's your 1st time to Thailand so I highly doubt you will be asked to show it, but given the poor exchange rate you'll get for SEK here it would probably be worth you bringing in something like USD not only cover you if you are asked but to give you something to exchange where you won't get so hammered by the FX rates.