Does anyone know why my refund for this year is less than the previous year if nothing changed? when calculating my refund in another website I get a much higher amount?

We cannot see your screen, your tax return or your account.  Have you entered ALL of your 2024 information?  All your income, etc.? 

There are a lot of variables that affect your refund or tax due including how much you earned, how much tax you had withheld, your filing status, the number of dependents you claim, your deductions and credits, etc.  You may have lost Earned Income Credit or the Child Tax Credit— did a child turn 17?  If you received the EIC last year, remember that changes in the amount you earn have a big effect on the amount of EIC you can get. (Sometimes earning more money means less EIC)  Are you 65 or older ?  If so, your standard deduction is higher. Everyone has a higher standard deduction now so it is harder to use itemized deductions.

And of course, always check your own data entries, looking for errors such as misplaced decimals or extra zeros.

https://ttlc.intuit.com/turbotax-support/en-us/help-article/tax-refund/refund-go-compared-last-year/L97JmhUbi_US_en_US?uid=ld9ijm41

Print out 2023  and 2024  and compare them side by side to see what is different. 

https://turbotax.intuit.com/tax-tips/tax-payments/video-why-would-i-owe-federal-taxes/L3VXudPiN