Converters & Encoders

164 free converters & encoders tools in the Developer Tools collection — every one runs in your browser with no signup and no uploads. Page 1 of 2.

A1 ↔ R1C1 Notation Converter

Switch spreadsheet cell references between A1 and R1C1 style

Arbitrary Base Converter

Convert any integer between bases 2 through 36 instantly

ASCII / Unicode Code to Character

Convert a decimal or hex code point to its character

Audio Sample Rate Converter

Resample audio to 44100 / 48000 / 22050 Hz in your browser

B-Encoding (RFC 2047) Encoder

MIME header word encoding: =?UTF-8?B?...?= Base64 variant

Base122 Encoder/Decoder

Experimental ultra-dense 7-bit encoding for HTML and JS embedding

Base36 Encoder and Decoder

Encode integers to compact alphanumeric base-36 and decode them back

Base45 Encoder/Decoder

Compact QR-code-friendly encoding used in EU COVID passes

Base62 Encoder/Decoder

URL-safe alphanumeric encoding — 0-9, A-Z, a-z only

Base91 Encoder/Decoder

High-density printable encoding — denser than Base64

Base91 Encoder/Decoder

Encode binary data with the efficient Base91 alphabet

Baudot / ITA2 Encoder

Encode text to 5-bit Baudot teleprinter codes

Baudot / ITA-2 Encoder

Encode ASCII text to Baudot/ITA-2 5-bit teleprinter code

BCD (Binary-Coded Decimal) Converter

Encode decimal digits as 4-bit BCD nibbles

Excess-3 BCD Converter

Encode decimal digits in Excess-3 (Stibitz code) BCD format

Bech32 Encoder/Decoder

SegWit Bitcoin address and Lightning invoice encoding with BCH checksum

Bencode Encoder/Decoder

BitTorrent's bencode: strings, integers, lists, dicts

Big5 Encoder/Decoder

Traditional Chinese Big5 byte encoding and decoding

Binary Text Converter

Convert text to and from 8-bit binary 01010100 01100101…

camelCase Converter

Convert space, snake, or kebab text to camelCase identifier format

Caverphone Encoder

New Zealand phonetic encoding — better for NZ/Aus names

TLS Certificate Decoder (PEM)

Paste a PEM certificate and see subject, SANs, validity, and signature algorithm

Character Frequency Map

Count every character and show descending frequency table

Character to ASCII / Unicode Code Converter

Get the decimal, hex, and octal codes for any character

Chord Keyboard Encoder

Map letters to stenography-style chord key combinations

Unicode Code Points to UTF-8

Compose Unicode code point sequences back into readable text

Common Port-to-Service Lookup

Common TCP/UDP ports with service name, protocol and typical process name.

TCF Consent String Encoder (IAB v2.x)

Build and encode a valid IAB TCF v2 consent string from selected purposes and vendors

Cron Expression to Human Text

Translate a cron schedule expression into plain English

Data URI Encoder

Encode text or binary to a data: URI for inline embedding

Data URI to File Converter

Decode a base64 data URI and download the binary file

Decimal Degrees ↔ Degrees Decimal Minutes

Convert between DD and DDM coordinate formats

Decimal Char Code Converter

Convert text to space-separated decimal char code points

DMS to Decimal Lat/Lng Converter

Convert degrees, minutes, seconds coordinates to decimal form

.NET DateTime Ticks Converter

Convert .NET DateTime ticks of 100-ns intervals to calendar dates

Double Metaphone Encoder

Primary and alternate phonetic codes for ambiguous pronunciations

EBCDIC ↔ ASCII Converter

Convert between IBM EBCDIC and ASCII character encodings

EBCDIC Encoder/Decoder

Convert ASCII text to IBM EBCDIC code points and back

ECEF to Lat/Lng Converter

Convert Earth-Centered Earth-Fixed XYZ to lat/long/altitude

Epoch Unit Converter

Convert epoch timestamps between seconds, ms, µs, and ns

Excel Column ↔ Number Converter

Convert Excel column letters (A, AB, ZZZ) to column numbers

Excel Serial Date Converter

Convert Excel and Lotus serial date numbers to calendar dates

Fixed-Point Converter

Convert real numbers to signed Qm.n fixed-point binary representation.

GB2312 / GBK Encoder/Decoder

Simplified Chinese GBK byte encoding and decoding

Geo URI Encoder

Format lat/lon/altitude as RFC 5870 geo: URI

GPX to FIT Converter (Garmin)

Convert a GPX track to a Garmin .fit activity file — entirely in your browser.

GPX to KML Converter

Convert GPX tracks and waypoints to Google Earth KML — fully private

Gray Code Converter

Convert binary integers to/from reflected Gray code

Gray Code Converter

Convert integers to Gray code and back — single-bit transitions

Hamming(7,4) Encoder/Decoder

Add error-detecting parity bits using Hamming code

.htaccess to Nginx Rewrite Converter

Convert Apache .htaccess RewriteRule directives to Nginx config

HTML Form URL Encoding

Encode form data using application/x-www-form-urlencoded rules

HTML to PDF Converter (Local Print)

Save any pasted HTML as a PDF using the browser's print-to-PDF engine.

Human Text to Cron Expression

Convert plain-English schedules into valid cron syntax

IPv4 Address ↔ Decimal Converter

Convert IPv4 dotted-quad notation to/from 32-bit decimal

IRI Encoder (RFC 3987)

Percent-encode an IRI to URI, preserving Unicode path chars

ISO 3166 Country Code Converter

Convert between ISO 3166-1 alpha-2, alpha-3, and numeric country codes.

ISO-8601 Duration Converter

Parse and convert ISO-8601 duration strings like P1Y2M3DT4H

kebab-case Converter

Convert text to lowercase-kebab-case for CSS and URLs

KML to GPX Converter

Convert Google Earth KML to GPX for Garmin, Strava and mapping apps

KOI8-R Encoder/Decoder

Russian Cyrillic KOI8-R byte encoding to hex and back

Lat/Lng to DMS Converter

Convert decimal latitude/longitude to degrees, minutes and seconds

Lat/Lng to ECEF Converter

Convert WGS-84 lat/long/altitude to ECEF Cartesian XYZ

Lat/Lng to Maidenhead Locator

Convert coordinates to a Maidenhead ham-radio grid square

Lat/Lng to MGRS Converter

Convert coordinates to a Military Grid Reference System string

Lat/Lng to Plus Code Converter

Encode coordinates as an Open Location Code (Plus Code)

LEB128 Encoder/Decoder

Encode integers to WASM-style Little Endian Base 128 format

Line Ending Converter (CRLF / LF)

Switch between Windows CRLF, Unix LF, and classic Mac CR

Mac Absolute Time Converter

Convert Apple CFAbsoluteTime in seconds since 2001-01-01 to dates

Maidenhead Locator to Lat/Lng

Convert Maidenhead grid square references to lat/long coordinates

Mailto URI Encoder

Build a mailto: URI with to/cc/bcc/subject/body encoded

Metaphone Encoder

More accurate phonetic encoding than Soundex for English words

MGRS to Lat/Lng Converter

Convert MGRS grid references back to decimal lat/long

Morse Code Encoder/Decoder

Convert text to and from International Morse Code dots and dashes

Netstring Encoder/Decoder

Encode strings in Bernstein's length:data, netstring format

NYSIIS Encoder

New York State Identification and Intelligence System phonetic code

Octal Text Converter

Convert text to octal byte values — like \033 in shell scripts

Octal to Binary Converter

Translate base-8 octal numbers into binary bit strings

Octal to Decimal Converter

Convert base-8 octal numbers to base-10 decimal

One's Complement Converter

Flip every bit to compute the one's-complement binary of an integer.

OpenAPI Spec to Markdown Docs

Generate a Markdown API reference from an OpenAPI YAML or JSON spec.

Ordinal Date Converter

Convert between calendar dates and ISO ordinal dates (YYYY-DDD)

PascalCase Converter

Convert text to PascalCase — every word capitalised, no separators

PDF to Plain Text Extractor

Extract readable text from a PDF file — private, no upload required

URL Percent-Decoder

Decode percent-encoded URL characters back to plain readable text

URL Percent-Encoder

Percent-encode special characters in a URL or URI component

Plus Code to Lat/Lng Converter

Decode a Plus Code back to decimal lat/long coordinates

Google Polyline Decoder

Decode a Google encoded polyline string into lat/long points

Google Polyline Encoder / Decoder

Encode lat/lon pairs to Google Encoded Polyline strings, and back

Google Polyline Encoder

Encode a list of lat/long points as a Google encoded polyline

Postman Collection to OpenAPI Converter

Convert a Postman Collection v2.1 JSON to an OpenAPI 3.0 YAML spec

Q-Encoding (RFC 2047) Encoder

MIME header word encoding: =?UTF-8?Q?...?= for non-ASCII

QR Code Decoder

Decode a QR code image locally — no upload, no third-party API.

RFC-2822 Date Converter

Convert between RFC-2822 email date format and ISO dates

RFC-3339 Date Converter

Convert between RFC-3339 timestamp strings and other formats

ROT-13 Encoder/Decoder

Apply the ROT-13 Caesar cipher substitution to any text

Run-Length Encoding (RLE)

Compress repeated runs: AAABBC → 3A2B1C

SCREAMING_SNAKE_CASE Converter

Convert text to UPPER_SNAKE_CASE for constants and env vars

Sexagesimal (Base-60) Converter

Convert integers to and from base-60 Babylonian sexagesimal notation.

Shift-JIS Encoder/Decoder

Show Shift-JIS (CP932) byte sequences for Japanese text