45 small tools, zero signup.
The same plain, no-nonsense thinking behind the apps, in calculators you can use right now. Everything runs in your browser. Nothing is saved, nothing is sent, no account needed.
Install them as apps
Related tools, bundled into free apps that share what you enter. Add to your home screen or dock, use offline, keep everything on your device.
Tech 7 tools
Buy smarter and run your Apple gear with confidence.
How many GB you really need, based on how you use your phone.
On-device apps keep your data on the phone instead of a server, and that needs room. We built this after watching people buy the wrong size twice.
Should you install the iOS beta? An honest five-question call.
Every app we ship gets tested against each iOS beta, so we learned the hard way which betas are safe on your daily phone.
Replace the battery now, soon, or ride it out.
Background features like alerts and Live Activities lean on the battery. Worth knowing where yours stands before you blame an app.
See if your device supports it and what runs on-device.
We build apps like VeraCast and DayCast that run AI locally on your device, never on a server. Check whether your iPhone supports it here.
Related app: VeraCastKeep your iPhone or buy the new one, compared per month of use.
Every September the question comes back. Trade-in, repairs, and years of use, divided out honestly.
Related app: DayCastYour daily average, projected across the waking years you have left.
The number behind the tagline on the homepage. Kynd exists for the days the phone wins.
Related app: KyndLatest betas, expected RC and release dates, and what your next update is.
Every app in the lineup is tested against each beta. This is the calendar I keep for myself.
Related app: VeraCastPrivacy 5 tools
Everything here runs in your browser, we could not see your data if we wanted to.
Strong, memorable passphrases plus a password strength checker.
Same rule as our apps: your data should not have to leave your device to be useful. This one never sends a thing.
See the hidden GPS and device data inside your photos.
Renewl and Solecito read images entirely on-device with Apple's Vision framework. This shows you what is hiding in a photo before you share it.
Related app: RenewlSixteen people-search sites, a direct opt-out link each, progress saved on your device.
Your address should not be a $2 lookup. Same rule as the apps: nothing leaves your device, including this checklist.
Related app: RenewlA 10 minute settings audit with a score.
The settings audit we run on our own phones. It is the same standard we hold the apps to, no analytics SDKs, no ad SDKs, no data sold.
Our standardsA risk score from six habit questions. You never type a password.
Companion to the passphrase generator: which fix to do first, and why the email account is the whole game.
Investing 6 tools
Calm, long-term money math for buy and hold investors.
Watch reinvested dividends compound over 5 to 40 years.
The math behind Holdwise, our dividend tracker. See the snowball here, then track your real one in the app.
Related app: HoldwiseHow big a portfolio you need for dividends to cover your bills.
Holdwise exists to answer this question with your actual holdings. This gives you the number in 30 seconds.
Related app: HoldwiseFind out if you can stop contributing and still retire on time.
DayCast tracks net worth privately on your device. This tool is the milestone that number is walking toward.
Related app: DayCastWhich account should hold each fund, taxable, Roth, IRA, 401(k), HSA.
A question our own investing apps kept raising, so we wrote the answer down.
See your drift from target and the trades to fix it.
Calm, once-a-year portfolio maintenance, the same buy-and-hold approach Holdwise is built around.
Related app: HoldwiseWhat a fund fee really costs over decades of compounding.
Fees are the one investing variable you fully control. Worth seeing what a 0.5% difference really costs.
Subscriptions 3 tools
See what those recurring charges really cost.
Total your subscriptions by month, year, and decade.
Renewl scans your receipts and warns you before a renewal hits. This is the total you are trying to bring down.
Related app: RenewlThe exact cancel-by date, a reminder, and a calendar file.
Renewl reads the trial end date off a screenshot. This is the manual version for one trial.
Related app: RenewlThe break-even month for the yearly plan, and what quitting early costs.
The math Renewl shows for every plan you track, for one plan you are deciding on.
Related app: RenewlWork and pay 8 tools
Plain-language pay math. General information, not legal advice.
Gross pay with overtime at time and a half over 40 hours.
The calculator that turned into Plantilla, our workers' rights and pay companion, now in ten languages.
Related app: Plantilla HubProject your paid time off balance across the year.
Written by an HR generalist who answers this question weekly. Plantilla does it with your real schedule.
Related app: Plantilla HubA quick exempt vs non-exempt check under federal rules.
The exempt vs non-exempt question behind Plantilla. General information, not legal advice.
Related app: Plantilla HubLast hours, overtime, unused PTO, and when your state says it is due.
I process these every month. The PTO payout rule is the part everyone gets wrong.
Related app: Plantilla HubNight and weekend premiums with overtime done the way the FLSA requires.
The differential belongs in your overtime rate. A lot of payroll systems miss it; this one does not.
Related app: SteadyFive questions, the same ones HR checks, with the reason behind the answer.
Plantilla has the full FMLA quiz in ten languages and what to do if the answer is no.
Related app: Plantilla HubEvery version of the number: hourly, weekly, biweekly, monthly, yearly.
The front door to the pay tools. Real hours and real weeks, not the 2,080 shortcut.
Related app: Plantilla HubEvery line on a US pay stub explained in plain English and plain Spanish.
Half the pay stub questions I get arrive in Spanish. Plantilla scans the real stub and does this line by line.
Related app: Plantilla HubHealth 6 tools
Everyday numbers explained plainly. Not medical advice.
How much caffeine is still in you at bedtime.
Steady helps shift workers sleep on a schedule nobody designed for them. Caffeine timing is half that battle.
Related app: SteadyBest bedtimes and wake times around 90 minute cycles.
Steady plans naps and sleep windows around real shift patterns. This is the simple version of the same math.
Related app: SteadyA sensible daily target without the hydration hype.
VitalCast reads your Apple Health data on-device and explains it plainly. Same idea, one number at a time.
Related app: VitalCastYour five training zones from age and resting heart rate.
VitalCast turns your Apple Health numbers into a briefing you can act on. Zones are a good place to start.
Related app: VitalCastSeven nights in, a debt out, and a recovery plan that does not move your clock.
Steady scores fatigue from your actual shift pattern. This is the one-week version.
Related app: SteadyDistance and an honest calorie estimate from your height and weight.
VitalCast reads your Health steps on-device and explains them. This is one number from that briefing.
Related app: VitalCastParents and kids 3 tools
Bedtimes, books, and the first money lessons. From the same desk as the picture books.
A bedtime window from wake-up time and pediatric sleep guidelines, naps included.
Written next to the Hush, Little Garden books. Steady does the same math for the parent on shift.
Related app: SteadyThe studio's books filtered by your kid's age and what they are working through.
Every title has an age band and a theme. This narrows the shelf to the ones that fit tonight.
Our standardsChores times a rate, or a flat allowance, split into save, spend, and give jars.
ChoreSight closes a chore with a live photo. This is what the chore is worth, and where it goes.
Related app: ChoreSightPets 5 tools
For the dogs and cats who run our households.
Your dog or cat's age in honest human years.
VitalLedger keeps every vaccine, vet visit, and weight for every pet in the house. Age is where most of those decisions start.
Related app: VitalLedgerCups per day from weight, life stage, and your food's calories.
Built for Sophie and Luna first. VitalLedger tracks the weight this portion is meant to hold steady.
Related app: VitalLedgerA fast lookup of safe, risky, and toxic foods for dogs and cats.
The lookup we wanted at 9pm on a Sunday. VitalLedger keeps the vet records for the times it goes wrong.
Related app: VitalLedgerA dated core vaccine timeline from the birth date, with a calendar export.
VitalLedger keeps the certificates this schedule produces, and shares them by QR code with the sitter.
Related app: VitalLedgerWhat a dog or cat really costs per month, with the vet and setup costs people forget.
VitalLedger tracks every pet expense next to the vet records. This is the estimate before you adopt.
Related app: VitalLedgerFun 2 tools
Because not every calculator has to be responsible.
Harry Potter, the MCU, Star Wars, Middle-earth. Total runtime and finish time.
No app tie-in, we just wanted to know if the whole MCU fits in a long weekend.
A simple Pomodoro timer for focused work and breaks.
Kynd is our focus app for ADHD brains, no streaks and no shame. This is the timer, stripped down.
Related app: KyndContact
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