Calculate your exact age, count words, shrink a photo for upload, check a percentage, a BMI, or generate a strong password. Six tools, zero installs — and nothing you type or upload ever leaves your device.
No tool matches that search — try “age”, “word”, “image”, “percent”, “bmi” or “password”.
Enter a date of birth to get the exact age in years, months and days — plus total days lived, the weekday you were born on, and a countdown to the next birthday. Handy for forms, school admissions, job applications and eligibility checks.
Paste or type your text and watch the counts update live — words, characters, sentences, paragraphs, reading time and your most repeated words. Built for essays, articles, speeches, resumes and social posts with length limits.
Shrink JPG, PNG or WebP photos so they fit upload limits on forms, job portals, email and websites. The image is processed on your own device — it is never uploaded to a server.
Three everyday percentage jobs in one place: find a percentage of a number (discounts, tips, tax), find what percentage one number is of another (scores, shares), and measure percentage increase or decrease (price changes, growth).
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Results update as you type. Example: 20% of 150 = 30 — the discount on a $150 item at 20% off, leaving $120 to pay.
Body Mass Index is a quick screening number based on height and weight. Enter yours to see your BMI, its standard category, and the healthy weight range for your height. It is a general guide, not a medical diagnosis.
Standard adult categories: under 18.5 underweight · 18.5–24.9 healthy · 25–29.9 overweight · 30 and above obese. BMI does not measure body fat directly — athletes and pregnant people can score outside these bands while healthy. Talk to a clinician for personal advice.
Create a strong, random password using your browser's built-in cryptographic randomness. Passwords are generated on your device and are never sent anywhere — close the tab and they are gone, so save yours in a password manager.
Calculators built for US workers, one new tool each week. They run in your browser, just like the tools above.
Work out time-and-a-half pay at 1.5× after 40 hours a week — regular pay, overtime pay and total gross pay for your week.
Every tool on this page runs on the same simple principle: the calculation happens inside your own web browser, the moment you ask for it.
Choose a date, paste some text, or drop in a photo. There is no account to create and nothing to install.
The maths, counting and image processing all run locally on your device. Your files and text are never uploaded to a server.
See the answer, copy it, or download the finished file. When you close the tab, your input is gone with it.
ToolStack is a small collection of free online tools for everyday jobs: working out an exact age for a form, checking the length of a piece of writing, shrinking a photo that is too large to upload, doing a quick percentage, checking a BMI, or making a password that is actually strong.
The tools were designed around three rules. They must be fast — the answer appears the moment you enter your input. They must be private — everything runs in your browser, so your text, dates and images are never uploaded anywhere. And they must be free without tricks — no accounts, no watermarks, no “premium” version hiding the useful part.
ToolStack is published by the team behind the AI WorkStack YouTube channel, which makes practical tutorials about AI tools and everyday productivity for a US audience. Tool requests and corrections are welcome — see the Contact section below.
Last updated: 14 November 2026. This policy explains what happens to your information when you use ToolStack.
All ToolStack tools run entirely in your web browser. The dates, text, numbers and images you enter are processed on your own device and are never transmitted to, or stored on, any server. When you close the page, that input no longer exists anywhere.
ToolStack is supported by advertising served through Google AdSense. When ads are active, Google and its partners may use cookies to serve ads based on your prior visits to this and other websites. You can opt out of personalised advertising at Google's Ads Settings page, and you can block or delete cookies in your browser settings at any time. Blocking cookies does not affect any tool on this page — the tools work without them.
ToolStack uses Google Analytics 4 to understand how the site is used. It records aggregate information only — such as which pages are visited, which tools are popular, and the country a visit came from — and never the content you type into a tool. Analytics cookies are set only if you accept them in the cookie banner shown on your first visit; if you decline, no analytics cookies are set and no visit data is sent. You can change your choice at any time by clearing this site's data in your browser settings.
ToolStack is a general-audience utility site and does not knowingly collect information from children under 13.
If this policy changes, the updated version will be posted on this page with a new “last updated” date.
Found a bug, got a wrong result, or want to request a new tool? The fastest way to reach the ToolStack team is through the AI WorkStack channel: