Instantcalcs
Free online calculators for math, finance, health, pregnancy and more, with instant results and no signup required.
Health & Fitness·Productivity·Finance
What is Instantcalcs?
InstantCalcs is a free website offering 98 online calculators covering math, finance, health, pregnancy, conversion, construction, food and other topics. Each calculator gives instant results, so users can get an answer without waiting or creating an account.
The site is aimed at anyone who needs a quick calculation, whether that is checking a percentage, estimating a loan figure, working out a body mass index, or estimating an ovulation window. The page highlights popular tools such as BMI calculators for men and women, an ovulation calculator, percentage and percentage increase calculators, and a fraction to percent converter.
What sets InstantCalcs apart, according to its own messaging, is simplicity: no signup, no clutter, and a free-to-use format. Calculators are organized into categories so visitors can browse by topic or search for a specific tool.
The site also lists health-focused options such as ABSI, FFMI, adjusted body weight and ideal weight calculators, which are described as based on standard formulas. Users should treat results as estimates and consult a professional for medical or financial decisions.
Ready to launch?
Submit your product and get discovered by builders and creators worldwide.
Launch Now
FounderPlaybooks.
What other founders did to grow.
2722 dispatches from hundreds of founders, pulled from the week's best podcasts.
I ran the numbers and it was like 4% or 4 and a half% had any kind of audience I mean any type of social podcast YouTube anything before they built their businesses... it's a fuck ton of work it's way more work way more work for the reward than SEO or cold Outreach
For B2B SaaS, audience building is overrated as a customer acquisition channel
Only ~4.5% of Tiny Seed's 150+ funded companies had any meaningful audience (social/podcast/YouTube/newsletter) before launching. The rest used SEO, cold outreach, integrations, in-person events, and affiliate programs — all hour-for-hour more efficient than building a personal brand. If you're selling to indie hackers, audience works because that's where they hang out. Outside that niche, lean on the boring marketing channels and stop tweeting to crickets.
it's a subscription model we have a 3-day free trial on our yearly plan and then our monthly plan is just build monthly for our yearly it's $40 and for the monthly it's 10 bucks a month
Run A Yearly Plan With A 3-Day Free Trial To Push New Users Past The Monthly
Coherence monetizes through a subscription with two clearly separated tiers: a yearly plan at $40 fronted by a 3-day free trial, and a monthly plan at $10. Anchoring the trial only on the yearly plan pushes new users toward the higher-LTV annual commitment from day one.
There's a play for whatever you're stuck on.
Read all 2722 playbooks