Keyword and key phrase extraction from text with relevance scores (RAKE)

Matrix calculator for up to 8x8 - determinant, inverse, rank, trace, transpose and the solution of the linear system Ax = b with a square matrix

Superfund sites near an address or coordinates (EPA NPL) - status, distance, hazard score and cleanup dates

ITIS species taxonomy lookup - scientific name to taxonomic serial number, rank, full kingdom-to-species lineage, child taxa and common names in English and other languages

Tax-inclusive price calculator - pre-tax amount and embedded tax from a total and rate

Convert annual salary to hourly, weekly and monthly gross equivalents

Number toolkit - primality, prime factorization, divisors, totient, perfect or abundant class, roman numeral, English words, bases and gcd or lcm with a second number

Sales tax calculator from subtotal and rate - tax and total

Tip, tax and total bill calculator from subtotal, tax rate and tip rate

ClinicalTrials.gov study search by condition, drug or keyword - NCT id, status, phase, sponsor, enrollment, conditions and start date, filter by recruiting

Search Wikimedia Commons images - licence name and URL, author credit, description, dimensions, original file URL and 640px thumbnail for each file

Autonomous system holder and announced IP prefixes by ASN from RIPEstat - IPv4 and IPv6 ranges currently routed in BGP and registry block information

Check whether an IP is a current Tor exit node against the Tor Project bulk exit list, with the list size and a plain-language verdict for fraud screening

Check an IP against the Feodo Tracker botnet C2 list, Emerging Threats compromised hosts and the Tor exit list with a combined verdict and matches

Lobsters front page or any tag feed - hottest or newest stories with score, comment count, tags, submitter and discussion link

US nonprofit organization search by name and state - EIN, city, NTEE category and tax-exempt status from IRS Form 990 data via ProPublica Nonprofit Explorer

Map a medical condition name to ICD-10-CM and ICD-9 codes with consumer-friendly names and synonyms using the NLM Clinical Tables conditions list

Find the real and complex roots of a polynomial up to degree 6, with discriminant and vertex for quadratics and a readable form of the equation

Binomial, Poisson and normal distribution probabilities - exact, at most, at least, ranges, z-scores and quantiles with mean and standard deviation

Drug name to RxNorm concept lookup - RxCUI, ingredient, brand names and clinical drug components for brand or generic medication names, NLM source