Start here: https://earthexplorer.usgs.gov/
Landsat 8 images have mostly 30m resolution.
If you are looking for earlier images, you will have to match it with the corresponding satellite. Thereafter, the bands and resolutions will have to be recalibrated too.
To check on the satellite and bands, start here:
https://landsat.gsfc.nasa.gov/a-landsat-timeline/
| Bands | Wavelength (micrometers) |
Resolution (meters) |
|---|---|---|
| Band 1 – Coastal aerosol | 0.43-0.45 | 30 |
| Band 2 – Blue | 0.45-0.51 | 30 |
| Band 3 – Green | 0.53-0.59 | 30 |
| Band 4 – Red | 0.64-0.67 | 30 |
| Band 5 – Near Infrared (NIR) | 0.85-0.88 | 30 |
| Band 6 – SWIR 1 | 1.57-1.65 | 30 |
| Band 7 – SWIR 2 | 2.11-2.29 | 30 |
| Band 8 – Panchromatic | 0.50-0.68 | 15 |
| Band 9 – Cirrus | 1.36-1.38 | 30 |
| Band 10 – Thermal Infrared (TIRS) 1 | 10.6-11.19 | 100 |
| Band 11 – Thermal Infrared (TIRS) 2 | 11.50-12.51 | 100 |
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