Browse every ISO 639-1 two-letter language code in one searchable directory — English name, native endonym, ISO 15924 writing system, text direction (LTR/RTL), primary country and how many regional locale variants each language has. Filter by script, toggle RTL-only and copy codes instantly. In your browser, free.

Everything runs in your browser from a built-in ISO database — no uploads, no requests, no tracking.

176
Languages
28
Writing systems
11
Right-to-left
443
Locale variants
Code Name Native name Script Direction Primary country Variants
No languages found
Try a different code, name or native spelling, or reset the filters.

About Language Codes (ISO 639)

The Language Codes directory lists every ISO 639-1 two-letter language code in one searchable table. Each row pairs the code with the language’s English name and its native endonym — Deutsch, 日本語, العربية — plus its writing system (ISO 15924 script code), text direction, primary country and the number of regional locale variants it has.

These codes are the backbone of software localization: they appear in HTML lang attributes, hreflang tags, Accept-Language headers, translation file names and locale identifiers like fr_CA. Developers and translators use the directory to confirm that Japanese is ja (not jp) or that the code for Persian is fa — the lookups that are easy to get subtly wrong.

Filters go beyond plain search: restrict the table to a single script, or toggle “right-to-left only” to isolate RTL languages when planning bidirectional layout support. Summary stats count the languages, writing systems, RTL languages and locale variants covered, and every code copies with one click. Everything runs in your browser.

How to use Language Codes (ISO 639)

  1. Search by code, English name or native name — for example fr, Spanish or 日本語.
  2. Filter by writing system, or enable “Right-to-left only” to see just the RTL languages.
  3. Read each row: code, name, endonym, script, direction, primary country and variant count.
  4. Click the copy button to grab the exact two-letter code for your markup or configuration.

Frequently asked questions

ISO 639-1 is the two-letter set (en, fr, ja) used across the web and most software. ISO 639-2 and 639-3 use three letters and cover far more languages. This directory lists the two-letter 639-1 codes, which is what HTML, HTTP and most locale systems expect.

A language code combined with a country code, such as fr_CA for Canadian French or pt_BR for Brazilian Portuguese, capturing regional differences in spelling, vocabulary and formatting. The variants column shows how many regional locales each language commonly has.

Toggle the “Right-to-left only” filter. It isolates the RTL languages — written in scripts like Arabic and Hebrew — which is exactly the list you need when checking whether an interface requires bidirectional layout support.

It names each language’s primary writing system using its ISO 15924 code — Latin, Cyrillic, Arabic, Han and so on. You can filter the whole table by script, which helps when choosing fonts or planning text rendering.

Because ISO 639-1 codes identify languages, not countries — jp is the country code for Japan under a different standard (ISO 3166). Mixing the two is a classic localization bug, and checking the directory takes seconds.

Yes, completely free. The whole ISO database ships with the page — searching, filtering and copying run in your browser with no requests and no tracking.

Need help?
Found an issue with this tool? Let our team know.
Report an issue

Add this free tool to your own website — copy and paste the code below.