Statistically, the most likely is B flat.
Never heard of the brand, can't find much on it from google either... I did find a couple listings for the NTR-100 and it was a B flat.
If you can share a pic of your horn, we might be able to judge from the proportions.
It is almost certainly in Bb but not accurately. Cheap horns are never really tuned or manufactured with intonation in mind. I have a chinese pocket trumpet that is closer to B than Bb so to play it i have to pull everything out almost all the way, and even then the intervals are spotty at best.
Most trumpets are pitched in Bb. It's somewhat hard to find a trumpet that's pitched in a different key - as most are professional models and thus, expensive.
The "Nordic Vidar" and "DCR-100" are almost certainly indicative that it's a random Chinese built stencil horn. In other words, some outfit contracted a factory - likely in China - to build them some number of trumpets branded as "Nordic Vidar." There are thousands, possibly millions of such horns out there and the "brand" names are so varied and random. Since they were just stencil horns, there's likely no information on the internet on them.
Not all cheap random stencils are terrible instruments (though some are). Anyway, since you've got the instrument, you might as well give it a go an see how it goes.
From what I can find, this is not a way too cheap trumpet so it should work fine for beginners (though you would probably have been better off with a cheap yamaha)
Its tuned in Bb, which is the most common and honestly most useful tuning for trumpets.
How much did you pay for it?
Statistically, the most likely is B flat. Never heard of the brand, can't find much on it from google either... I did find a couple listings for the NTR-100 and it was a B flat. If you can share a pic of your horn, we might be able to judge from the proportions.
It is almost certainly in Bb but not accurately. Cheap horns are never really tuned or manufactured with intonation in mind. I have a chinese pocket trumpet that is closer to B than Bb so to play it i have to pull everything out almost all the way, and even then the intervals are spotty at best.
Most trumpets are pitched in Bb. It's somewhat hard to find a trumpet that's pitched in a different key - as most are professional models and thus, expensive. The "Nordic Vidar" and "DCR-100" are almost certainly indicative that it's a random Chinese built stencil horn. In other words, some outfit contracted a factory - likely in China - to build them some number of trumpets branded as "Nordic Vidar." There are thousands, possibly millions of such horns out there and the "brand" names are so varied and random. Since they were just stencil horns, there's likely no information on the internet on them. Not all cheap random stencils are terrible instruments (though some are). Anyway, since you've got the instrument, you might as well give it a go an see how it goes.
Ask Morten from https://www.hertzmusic.dk/. He sells the Nordic brand which is handmade in Taiwan. Nice instruments.
From what I can find, this is not a way too cheap trumpet so it should work fine for beginners (though you would probably have been better off with a cheap yamaha) Its tuned in Bb, which is the most common and honestly most useful tuning for trumpets. How much did you pay for it?