Where you might still buy them
The bad news is that, at this point, according to the American Astronomical Society, which heroically set up a comprehensive rundown of where to find them before they sold out, most of the ISO-compliant (more on that in a sec) eclipse glasses you could purchase online are gone. The AAS explained the situation in a note on its website: "It is now too late to buy solar viewers in time for August 21st. Virtually all vendors are sold out, whether or not they’re listed as such below. See our pinhole projection page for other ways to enjoy the partial phases of the eclipse."
There might be some hope to be found in brick-and-mortar stores, but you'll have to call ahead to specific locations to verify availability. According to the AAS, it's safest to buy glasses that comply to ISO standards in a physical store. The society has listed the following retail chains as reputable, reliable brick-and-mortar retailers.
- Best Buy
- Casey's General Store
- Hobby Town
- McDonald's (Oregon only)
- Pilot/Flying J
- Toys "R" Us
You might be able to score free glasses
There are a few different options for this still available. For starters, NASA will be giving out 1.5 million glasses at events and locations around the country. Use this guide to figure out the one closest to you.
There are also 6,900 libraries across the United States handing out solar eclipse glasses for events on Monday, thanks to help from NASA, Google, and the Gordon and Betty Moore Foundation. You'll want to use this map to learn where you can find them and when the events are scheduled.
Look out for fake eclipse glasses
It's important to make sure, no matter where you get your glasses from, that they are ISO-compliant. That refers to a very specific international safety standard, ISO 12312-2, which refers to filters used for direct viewing of the sun. There is a long answer to the question of what that means, helpfully also provided by the AAS, but the short answer is simple: look out for counterfeit glasses that shameless profiteers have used to flood the solar eclipse viewing market.
Moreover, it's easy enough for these shameless vendors to grab the ISO logo from the internet and stick it on their labels. The best possible recourse anyone can fall back on is abiding by AAS's list of reputable vendors when making your purchases. The organization cross-checks their ISO paperwork and has done the due diligence of making sure those vendors' glasses are actually safe. If you come across eclipse glasses that do not explicitly make clear that they meet the ISO 12312-2 standard laid out in 2015, do not use them to look at the sun during the eclipse. Remember: you will not feel your vision rapidly burn away.