Tools that just work
A set of handy online tools for PDFs, images and text. Everything runs right in your browser — no file uploads, no sign-up, free.
Tools by category
PDF documents — Merge, split or rotate a PDF right in your browser, no server upload.
Images and colors — Shrink file size, resize, convert format, work with color codes and check WCAG contrast.
Passwords and security — Generate a strong password, test an existing one, compute a hash or a unique UUID.
Working with text — Convert to upper/lower case, make a URL-friendly slug, count characters, check word frequency, or generate Lorem Ipsum.
Encoding and data — Base64, URL encode/decode, JSON formatting and number base conversion — the basic developer toolkit.
Conversions and calculations — Units, time, percentages, dates, age and days between dates.
Generators — A QR code for your website, business card or payment — in seconds, for free.
Image compression
Reduce the file size of a JPG, PNG or WebP image right in your browser.
Image format conversion
Convert an image between JPG, PNG and WebP right in your browser.
Resize image
Change an image's width and height right in your browser.
QR code generator
Create a QR code from a link or text and download it.
Merge PDF
Combine several PDF files into one right in your browser.
Split PDF (pick pages)
Pick specific pages from a PDF and download them as a new file.
Strong password generator
Create a strong random password right in your browser.
Character and word counter
Count characters, words, sentences and paragraphs in your text instantly and for free.
Lorem ipsum generator
Generate Lorem ipsum placeholder text with a chosen number of paragraphs.
Base64 — encode and decode
Encode or decode text to/from Base64.
Rotate PDF
Rotate all pages of a PDF by 90, 180 or 270 degrees and download.
Percentage calculator
Calculate percentages: what is X% of Y, X is what % of Y, percentage change.
UUID generator
Generate random version-4 UUIDs.
Color converter (HEX ↔ RGB)
Convert a color between HEX and RGB with a preview.
JSON formatter and validator
Format and validate JSON (pretty-print) right in your browser.
Time / Unix Timestamp Converter
Convert a Unix timestamp (seconds or milliseconds) to a readable date and back.
Word Frequency Counter
Count word frequency in any text free, right in your browser.
Slugify and Accent Remover
Free tool to turn text into a clean URL slug: lowercase, no accents, hyphens instead of spaces.
Password Strength
Check your password strength free in the browser.
Days Between Dates
Calculate the number of days and weeks between two dates for free.
Unit converter
Convert length, weight, temperature and volume between units.
BMI calculator
Calculate your BMI (body mass index) from height and weight.
Age calculator
Calculate exact age from a date of birth — years, months and total days.
Uppercase & lowercase
Convert text to UPPERCASE, lowercase, Sentence case or Title Case.
URL encode / decode
Encode or decode text for use in a URL (percent-encoding).
Hash generator
Generate a hash of text (SHA-256, SHA-1, SHA-512) right in your browser.
Number base converter
Convert numbers between binary, octal, decimal and hexadecimal.
Color contrast (WCAG)
Check the contrast ratio of text and background against WCAG (AA, AAA).
Date calculator
Compute a date after adding or subtracting a number of days.
Why Nástrojárna?
- 🔒 Privacy first. Files are processed on your device and sent nowhere.
- ⚡ Lightning fast. No waiting on a server — you get the result instantly.
- 🆓 Free, no account. Open it, use it, done.
- 🧩 29 tools in one place. From PDF to images to generators — no need to search elsewhere.