Free online tools for everyday tasks

Calculators, unit converters, text utilities, and developer tools that run entirely in your browser. No account, no uploads, no waiting.

Browse by category

Purpose-built tool collections. Each tool is a standalone page you can bookmark and share.

8 tools

Calculators

Everyday math, money, date, and time calculations with clear formulas and explicit edge-case handling.

7 tools

Converters

Length, weight, temperature, speed, area, volume, and recipe conversions built on exact unit definitions.

5 tools

Text Tools

Count words, change case, remove duplicate lines, sort lines, and compare text — all locally in your browser.

7 tools

Developer Tools

Format JSON, encode Base64 and URLs, generate UUIDs, convert timestamps, hash text, and test regular expressions.

5 tools

Image Tools

Compress, resize, crop, and convert images, plus generate QR codes, without uploading a single file.

3 tools

PDF Tools

Merge, split, and rotate PDF files entirely inside your browser.

Available now

Every tool below is live, tested, and runs locally in your browser.

Calculators

Percentage Calculator

Find X% of a number, work out what percent one number is of another, and calculate increases or decreases.

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Calculators

Discount Calculator

Work out the sale price, discount amount and total savings from one or two stacked percentage discounts, with optional sales tax.

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Calculators

Age Calculator

Calculate an exact age in years, months and days from a date of birth, with total months, weeks, days and the next birthday.

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Calculators

Date Calculator

Add or subtract years, months, weeks and days from a date, or calculate the exact difference between two dates.

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Calculators

Time Card Calculator

Track a week of shifts with breaks, overnight hours, overtime and an optional hourly rate.

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Calculators

Average Calculator

Calculate the mean, median, mode, range and standard deviation for a list of numbers.

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Calculators

Ratio Calculator

Simplify a ratio, find a missing value, scale a ratio to a total and split an amount proportionally.

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Calculators

Tip Calculator

Calculate the tip, total bill and per-person amounts, with tax-aware tipping and bill splitting.

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Converters

Length Converter

Convert millimetres, centimetres, metres, kilometres, inches, feet, yards and miles with adjustable precision.

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Converters

Weight Converter

Convert milligrams, grams, kilograms, tonnes, ounces, pounds, stone and US or UK tons.

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Converters

Temperature Converter

Convert Celsius, Fahrenheit and Kelvin in both directions, with absolute-zero validation.

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Converters

Speed Converter

Convert metres per second, kilometres per hour, miles per hour, feet per second and knots.

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Converters

Area Converter

Convert square millimetres, metres, kilometres, hectares, square feet, acres and square miles.

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Converters

Volume Converter

Convert millilitres, litres, cubic metres and US or UK cooking units such as cups, pints and gallons.

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Converters

Recipe Converter

Scale a recipe to a different number of servings and convert cooking units without inventing ingredient densities.

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Text Tools

Word Counter

Count words, characters, sentences, paragraphs and lines, with reading and speaking time estimates.

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Text Tools

Case Converter

Convert text to upper case, lower case, title case, sentence case, camelCase, snake_case or kebab-case.

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Text Tools

Remove Duplicate Lines

Remove duplicate lines from a list, with options for case, whitespace, empty lines and keeping the first or last copy.

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Text Tools

Sort Text Lines

Sort lines alphabetically or numerically, ascending or descending, with options for case, whitespace and empty lines.

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Text Tools

Text Diff Checker

Compare two texts line by line and see added, removed and unchanged lines, with optional case and whitespace ignoring.

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Developer Tools

JSON Formatter

Format, minify and validate JSON, with indentation, key sorting and precise error positions.

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Developer Tools

Base64 Encoder and Decoder

Encode text to Base64 or decode Base64 back to UTF-8, with URL-safe output and clear validation errors.

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Developer Tools

UUID Generator

Generate cryptographically random version 4 UUIDs in batches, with uppercase and hyphen options.

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Developer Tools

URL Encoder and Decoder

Percent-encode text for URLs or decode percent-encoded strings, with optional form-style plus signs for spaces.

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Developer Tools

Unix Timestamp Converter

Convert Unix timestamps in seconds or milliseconds to dates and back, with ISO, UTC and local time.

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Developer Tools

Hash Generator

Generate MD5, SHA-1, SHA-256 and SHA-512 hashes of text locally in your browser.

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Developer Tools

Regex Tester

Test JavaScript regular expressions against your text, with flags, match positions, capture groups and highlighting.

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Image Tools

Image Compressor

Compress JPEG, PNG and WebP images in your browser with adjustable quality, format and maximum width.

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Image Tools

Image Resizer

Resize JPEG, PNG and WebP images to exact dimensions or by percentage, preserving aspect ratio.

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Image Tools

Image Converter

Convert JPEG, PNG and WebP images in your browser, with quality control and transparency handling.

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Image Tools

Image Cropper

Crop JPEG, PNG and WebP images with a draggable box, aspect-ratio presets and exact pixel fields.

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Image Tools

QR Code Generator

Create QR codes for links or text with adjustable size, margin, error correction and colours, then download PNG or SVG.

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PDF Tools

Merge PDF Files

Combine two or more PDF files into one document in your browser, with drag-free ordering and page counts.

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PDF Tools

Split PDF

Split a PDF into single pages or custom ranges and download the results as separate files or a ZIP archive.

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PDF Tools

Rotate PDF

Rotate all or selected pages of a PDF by 90, 180 or 270 degrees in your browser.

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Your data stays in your browser

1123.net is a static site. Calculations, conversions, and text processing run in your browser using JavaScript. There is no application database, no account system, and no upload endpoint.

No sign-up, no email, no user profile.
No tool input is sent to our server or stored remotely.
The only third-party request is advertising, which is loaded outside the tool workspace.