The little box of tools
built for programmers
Format, decode, generate and inspect — all the tiny utilities you keep googling, in one fast, private, ad-free place.
Everything in the toolbox
Pick a tool and go — no accounts, no sign-up, no nonsense.
Network & DNS
9 toolsLook up what is actually configured, from the browser to the routing table.
IPv4 Subnet
CIDR calculator: network, broadcast, mask, host range and class.
IPv6 Tools
Expand & compress addresses, derive prefix range and host count.
DNS Lookup
Look up A, AAAA, MX, TXT, NS, SOA, CAA and more, plus reverse DNS.
DNS Propagation
Check what four public resolvers are serving right now, with the cache TTL.
Email DNS Check
Check SPF, DKIM, DMARC and MX, including the RFC 10-lookup SPF limit.
WHOIS / RDAP
Domain registrar, dates, EPP status codes and nameservers via RDAP.
IP Lookup
Geolocation, ISP, connection type, origin AS, reverse DNS and registry allocation.
ASN Lookup
Who operates an autonomous system, and every prefix it announces in BGP.
MAC Address Lookup
Find the manufacturer behind a MAC address, without sending it anywhere.
Convert & Time
5 toolsUnits, money, timestamps and schedules.
Unit Converter
Length, mass, temperature, volume, data, pressure and more — 13 categories.
Currency Converter
Convert between 30 currencies at recent market rates, with the fetch time shown.
Timezone
See one moment in six timezones at once, with daylight saving applied.
Epoch Converter
UNIX timestamp ⇄ date, both directions, in seconds and milliseconds.
Cron Parser
Translate cron expressions to plain English and preview next runs.
Generators
6 toolsMake something new — codes, identifiers, passwords, winners.
QR Code
Generate QR codes for text, URLs, Wi-Fi and contacts. Download SVG or PNG.
Barcode Generator
Code 128, EAN-13, UPC-A and six more. Download as SVG or PNG.
Password Generator
Generate strong passwords from selectable character sets, in your browser.
UUID Generator
Bulk-generate v4 / v7 UUIDs, ULIDs and nanoids. Copy in one click.
Lorem Ipsum
Generate placeholder text by word, sentence or paragraph.
Random Name Picker
Pick winners from a list of names — provably fair, with a verifiable mode.
Data & Formats
7 toolsRead, reshape and check structured text.
JSON Formatter
Beautify, minify and validate JSON. Tree view with collapsible nodes.
JSON Validator
Find the exact line, column and cause of a JSON syntax error.
SQL Formatter
Format and beautify SQL queries across multiple dialects.
CSV / JSON
Convert CSV to JSON and back, with quoted fields and delimiter detection.
YAML / JSON / TOML
Convert between YAML, JSON and TOML in any direction, with parse errors.
HTML / XML
Format HTML & XML, check XML well-formedness, encode/decode entities.
Markdown Preview
Live Markdown editor and previewer with table support.
Encoding & Security
8 toolsEncode, decode, hash and verify — all of it locally.
Base64 / Hex
Encode and decode Base64, URL, hex and binary in one place.
Number Base
Convert binary, octal, decimal and hex with bit widths and bitwise ops.
URL Parser
Parse a URL into parts, edit query params, encode & decode components.
ASCII Table
All 128 codes in dec, hex, octal and binary — with the control codes explained.
Hash Calculator
Calculate MD5, SHA-1, SHA-256, SHA-512 and Keccak-512 digests at once.
File Checksum
Verify a download's MD5, SHA-1, SHA-256 or SHA-512 without uploading it.
JWT Decoder
Inspect header, payload and signature. Verify HS/RS keys locally.
htpasswd Generator
Generate Apache htpasswd hashes (APR1-MD5, SHA-1) and verify a password against an existing hash.
Images & Design
5 toolsPixels and colour, without uploading anything.
Image Resize & Convert
Resize, compress and convert between PNG, JPEG and WebP. Strips EXIF.
EXIF Viewer & Remover
See what a photo reveals — GPS, time, device, owner — and strip it losslessly.
Color Converter
Convert HEX ↔ RGB ↔ HSL and build a tint and shade palette.
Contrast Checker
Check a text and background pair against WCAG AA and AAA, both text sizes.
SVG Optimizer
Minify and optimize raw SVG code to reduce file sizes.
Documents
3 toolsPDFs, rebuilt in your browser. Nothing is uploaded.
Text
5 toolsCompare it, match it, rename it.
Regex Tester
Live-match patterns with capture groups, flags and a cheat sheet.
Diff Viewer
Compare two texts side by side or inline, with word-level change highlights.
Case Converter
camelCase, snake_case, kebab-case, CONSTANT_CASE, Title Case and slugs.
Word Counter
Count words, characters, sentences and reading time as you type.
Morse Code
Translate text to Morse and back, and hear it played at any speed.
Dev & Web
4 toolsThe workbench odds and ends.
API Tester
Send GET/POST/PUT/PATCH/DELETE with custom headers and body, no proxy.
Code Playground
Live JSFiddle-style sandbox for HTML, CSS, and JS.
GitIgnore
Generate .gitignore templates for your tech stack instantly.
chmod Calculator
Convert between permission checkboxes, octal like 755 and rwxr-xr-x.
Why nyaa.tools?
The dev utilities you reach for daily, without the ads, paywalls or sketchy uploads.
Private by design
Almost every tool computes entirely in your tab — paste secrets without a second thought. The few that reach the network say so on the card. The DNS, WHOIS and ASN lookups and the API tester talk straight from your browser to the provider, so we never see those. The one exception is IP Lookup's geolocation, which asks nyaa.tools' own API because MaxMind needs a licence key — it says so in the tool.
Built for speed
Each tool loads only its own code, the page itself is a few dozen kilobytes, and nothing waits on a server round-trip to give you an answer.
Simple & focused
Small, focused utilities for everyday developer tasks — fast to open, easy to use, and free from distractions.
Built for the things you keep googling
nyaa.tools is a working developer's scratchpad. New tools get added as they turn out to be needed — and most of them run entirely on your machine.
Any tool can be embedded in your own docs, blog or wiki — open one and hit </> Embed for the snippet. It stays just as private inside an iframe.