Free satellite imagery is more available today than at any point before, and you do not need a budget to start working with it. Europe's Copernicus programme, the USGS Landsat archive, NASA's open data services and a handful of browser viewers built on top of them give you global coverage at 10 to 30 metre resolution, with no payment required for any of them. The trick is knowing which source fits your job, because each one has different strengths, different resolutions and different limits. Here are the ten free sources worth knowing in 2026.

1. Copernicus Browser: The Source of Truth for Sentinel Data

The European Union's Copernicus Data Space Ecosystem is the definitive source for Sentinel data. Sentinel-2 images every point on Earth at 10 metre resolution roughly every five days, and the browser searches, previews and downloads the full rasters. Sentinel-1 is a radar mission that images through cloud cover and at night, at 5 to 20 metre resolution. The raw data is free, and it arrives in formats built for remote-sensing specialists, so producing a usable image takes a few processing steps and the right software. If you want the data itself rather than a picture of it, start here. It is the reference standard that most other free tools draw on.

2. USGS EarthExplorer: The Longest Record There Is

EarthExplorer is the front door to the Landsat archive: 30 metre resolution reaching back to 1972, the longest continuous satellite record of Earth's surface. That depth is its superpower. If you want to track how a coastline, a forest, a glacier or a city has changed over decades, Landsat is the only free source that goes back far enough. Resolution is coarser than Sentinel-2, about 15 to 30 metres depending on the band, so a sports field is roughly one pixel, but for long-term change detection it is unbeatable. EarthExplorer also catalogs aerial photography, MODIS data and additional datasets, all available to download at no cost.

3. NASA Worldview: The Fastest Free Imagery

NASA Worldview shows near real-time satellite imagery, updated every few hours, from MODIS, VIIRS and other NASA sensors. It is a viewer rather than a download portal, and it is the fastest way to see what happened yesterday: a wildfire, a flood, a dust storm, a volcanic eruption. The resolution is coarse, 250 metres to 1 kilometre for most layers, so it is not the tool for field-scale work, but for situational awareness and for teaching, it is unmatched. NASA Earthdata Search, its companion, lets you search and download the underlying data for analysis.

4. LandViewer: The Beginner-Friendly All-Rounder

LandViewer combines free satellite images from different providers with a user-friendly interface and built-in visualisation and analysis tools. As of 2026 you can get the most recent free imagery from Landsat 7, Landsat 8, Sentinel-1, Sentinel-2, CBERS-4, MODIS, aerial data from NAIP and historical imagery from Landsat 4 and 5. You can download a free full or cropped natural-colour Sentinel image in JPEG, KMZ or GeoTIFF, and preview high-resolution commercial imagery before deciding whether to order it. It is the best free source for GIS beginners and for experts from other industries who do not use special GIS software but want updated satellite data with fast, accurate analytics included.

5. Google Earth Engine and Other Browser Tools

Google Earth Engine gives you the entire Landsat and Sentinel archives plus the computing power to analyse them in the cloud, without downloading a single file. It is free for research, education and non-commercial use, and it is the tool behind most large-scale satellite studies published today. For simple viewing, Google Earth itself is free on desktop and web, though it does not provide raw data for download. SkyFi Open Data brings free imagery from Sentinel-1, Sentinel-2 and free commercial samples into one platform, with an API for projects at scale, and it delivers imagery as pre-processed, view-ready images alongside the raw files. Pera Portal's free tier offers unlimited Sentinel-2 browsing with more than 45 pre-configured spectral indices such as NDVI, NDWI and EVI, computed in the browser with no setup and no credit card.

What Free Imagery Cannot Do

Free downloadable data tops out at 10 metre resolution with Sentinel-2: you can see fields and buildings as shapes, not details. You cannot task a free satellite, so if nothing captured your site cloud-free recently, there is nothing to download. And the newest sensors, including the NASA-ISRO NISAR radar mission that opened to the public in 2026 at 5 to 10 metre resolution, are still rolling out. For most jobs, though, the free tier is enough: Sentinel-2 wins on the balance of resolution and revisit, NASA Worldview wins on speed, EarthExplorer wins on historical depth, and LandViewer wins on ease of use. Start with the source that matches your question, download a scene, and open it in QGIS. The data is free, the software is free, and the only cost is your time.