Free tools
Free tools
Small, free calculators and checkers. No sign-up, nothing stored.
Best promo code calculator
Compare percent off, dollars off and free shipping to find the lowest checkout total.
Open the toolCoupon stacking calculator
See the real total when discounts stack, or choose the best single offer when they do not.
Open the toolFree shipping calculator
Compare adding an item to reach free shipping with paying the shipping charge.
Open the toolPromo code eligibility checker
Check whether a cart matches a code’s stated minimum spend, expiry and exclusions.
Open the toolStore promo code lookup
Find a store’s live codes, conditions and last recorded checkout verification dates.
Open the toolPeptide COA checker
Check a certificate of analysis line by line: identity, batch, content, purity, test date and lab.
Open the toolSubstack vs beehiiv cost calculator
Compare Substack's 10% cut with a beehiiv plan on your own subscriber and revenue numbers.
Open the tool