Tools That Run in Your Browser
Free, self-built utilities for text, hardware testing, and audio. No installs, no sign-ups, nothing ever leaves your device.
Every tool here was built to solve one specific, everyday problem well, not to upsell a bigger product. Whether you need a quick unit conversion, a way to test a new monitor for dead pixels, or a private place to strip metadata from a photo, you can open the tool and get an answer in seconds, with no account and no waiting on a server.
163 tools across 7 tags, and every one of them is free.
Runs in your browser
Most tools process everything locally. Nothing you type or upload has to leave your device.
Free, no catch
No paid tier, no usage caps, no watermarks on what you export or download.
No sign-up needed
Open any tool and use it right away. An account is optional, only for syncing across devices.
10 languages
The whole site and every tool are fully translated, switchable from the navigation bar.
Featured Tools
Text
Atbash Cipher Tool
Encode and decode text with the Atbash cipher in classic, digit, and Hebrew variants, with a live mirror-pair reference and character mapping table.
FreeCalculators
Astronomical Unit Converter
Convert astronomical distances between AU, light-years, parsecs, kilometers, and more, with light-travel time and a cosmic scale visualization.
FreeCalculators
Aspect Ratio Calculator
Compute missing dimensions from a ratio, simplify pixel dimensions to a ratio, or resize proportionally, with a live preview and common ratio presets.
FreeCalculators
ARM Mortgage Calculator
Model the worst-case payment scenario for an adjustable-rate mortgage, with payment shock, a year-by-year schedule, and a fixed-rate comparison.
FreeCalculators
Arithmetic Sequence Calculator
Calculate the nth term and sum of an arithmetic sequence, with a sequence preview, bar chart, and reverse lookup for a target value.
FreeCalculators
Arithmetic Mean Calculator
Calculate the arithmetic mean, median, mode, range, and both population and sample standard deviation of a dataset, with a dot plot and histogram.
FreeText
Argon2 Hash Generator
Generate and verify Argon2id/Argon2i/Argon2d password hashes entirely in your browser, with adjustable memory cost, time cost, and parallelism.
FreeCalculators
Area Calculator
Calculate the area of rectangles, triangles, trapezoids, circles, sectors, ellipses, and parallelograms, with a live diagram and instant unit conversions.
FreeCalculators
Arctan2 Calculator
Calculate atan2(y, x), the angle of a point in the Cartesian plane, with quadrant detection, normalized angle, and a step-by-step breakdown.
FreeCalculators
Arcsin Calculator
Calculate the arcsine (inverse sine) of a value in degrees or radians, with special-angle detection and a unit circle visualization.
FreeCalculators
Arccos Calculator
Calculate the arccosine (inverse cosine) of a value in degrees or radians, with special-angle detection.
FreeCalculators
Aquarium Volume & Stocking Calculator
Calculate aquarium water volume by tank shape and estimate a rough fish stocking capacity.
FreeCalculators
Aquarium Heater Wattage Calculator
Calculate the right heater wattage for your aquarium based on tank size and temperature gap.
FreeCalculators
AP Score Calculator
Estimate a rough AP exam score from your MCQ and FRQ results, clearly marked as unofficial.
FreeCalculators
APR to APY Calculator
Convert between APR and APY at any compounding frequency, with a comparison table and dollar example.
FreeCalculators
APR Calculator
Calculate the real APR of a loan including fees and discount points, right in your browser.
FreeCalculators
Appliance Energy Cost Calculator
Estimate the daily, monthly, and annual electricity cost of an appliance, with a running multi-appliance total.
FreeText
API Tester
Send HTTP requests to any API endpoint and inspect the response, right in your browser.
FreeCalculators
Apgar Score Calculator
Calculate and categorize a newborn Apgar score from its five clinical signs, right in your browser.
FreeCalculators
Antilog Calculator
Calculate the antilogarithm (inverse log) of a number for base 10, e, 2, or a custom base, right in your browser.
FreeHardware
Antenna Length Calculator
Calculate the physical length of a dipole, vertical, or loop antenna from an operating frequency, right in your browser.
FreeCalculators
Anova Calculator
Run a one-way ANOVA test with full statistics table, effect size, and a group comparison chart, right in your browser.
FreeCalculators
Annuity Payout Calculator
Calculate a sustainable payout amount from a balance, or how long a fixed payment will last, right in your browser.
FreeCalculators
Annuity Calculator
Project how a savings balance grows with regular contributions and compound interest, right in your browser.
Frequently asked questions
›Is WMW really free? What's the catch?
Yes, every tool is completely free with no usage limits, no watermarks, and no hidden paid tier. Most tools run entirely as JavaScript in your browser, so there is no server cost per use to recover, which is what lets us keep everything free.
›Do I need to create an account to use the tools?
No. Every tool works immediately with no sign-up. Creating a free account is optional and only unlocks a few conveniences, like syncing your favorites and recently-used tools across devices instead of storing them in this one browser.
›Is my data safe? Do you upload my files or text anywhere?
Most tools, especially anything working with images, audio, or sensitive text, process everything locally in your browser using standard web APIs and never send your file or input to a server. Any tool that does need a server round-trip says so directly on the page.
›What kinds of tools are available?
Calculators covering everyday math, finance, and health; text tools for counting, converting, and transforming; image editors for cropping, filtering, and adjusting; hardware and display test tools for checking a monitor, keyboard, or webcam; and generators for things like passwords, hashes, and random picks.
›Which languages is the site available in?
The interface and every tool are fully translated into 10 languages. Use the language switcher in the top navigation bar to change it at any time; your choice is remembered for future visits.