IRS Pub 501. Chart on page 12 and page 19 Gross Income Test. There may be other places too.
https://www.irs.gov/pub/irs-pdf/p501.pdf
Each year the amount changes. They have income less than
2024 $5,050
2023 $4,700
2022 $4,400
2021 $4,300
2020 $4,300
2019 $4,200
