I respectfully offer that the Better Business Bureau is not a reputable source. They rate companies and charities in the same way Yelp rates businesses. They offer fees for ratings and the complaint process does absolutely nothing. I'll let you do the google sleuthing on it, but please, do not use them for anything.

Charity Navigator, Candid, and ProPublica offer far better tools for assessing charity. If you're paywalled from navigating some of the tools provided by Candid or other big entities, you can try your local library as they'll sometimes have access.

Finally, the "best" charity in my line of work (I research these things) depends on three things:

1. % of contributions spent on administrative overhead
2. % of revenue spent on ED/CEO compensation
3. Measured program effectiveness in the service area

And you should absolutely read what @frog@beehaw.org has contributed. Clear mission/value/goal/program alignment, transparency, and accountability to the public are, generally, praise worthy organizations. Those that do not provide annual reports, 990s, and other important information on their websites are, in my research/experience, generally doing something questionable if not illegal.