How can I find out what my CEFR1 proficiency level in a language is, without going to a testing center and paying to take a test? Are there any good resources (free tests, online tests, etc.) or guidelines for this?
1 Common European Framework of Reference for Languages
DIALANG is a free language diagnosis system available from Lancaster University. It reports your level of skill against the Common European Framework (CEFR) for language learning. DIALANG languages are Danish, Dutch, English, Finnish, French, German, Greek, Icelandic, Irish-gaelic, Italian, Norwegian, Portuguese, Spanish and Swedish. DIALANG has instructions and tests in all these languages. Competences tested are reading, writing, listening, grammar and vocabulary, speaking is not tested. Appendix C of the CEFR contains the descriptors for self-assessment at series of levels adopted by the DIALANG Project of the European Commission for use on the Internet.
You will probably find more free tools online for specific languages, that will be more appealing to young learners but none are as elaborate as Dialang which was funded by a European programme.
The approach I would take is to find coursebooks teaching the language at the various levels, look through them, and estimate my level based on that. Once you have an idea of where you might be - for instance, either B1 or B2 - check a few cours books by other publishers in that range - that should help you narrow it down.
Typically a lot of research goes into making sure that a B1 coursebook has B1 level material. Make use of that!
Also keep in mind that talking to a native speaker might not actually help. Many native speakers have no idea about the CEFRL system - and aren't teachers.
One of the simplest options is to find a native speaker and start conversing. An advantage to this particular strategy is that if you have discipline-specific vocabulary you want to test, you can try to find a native speaker in that discipline to speak with.
If a native speaker isn't readily available, websites like italki offer 1-on-1 video lessons with native speakers around the world for a per-lesson fee. (That's not technically free, but it's not terribly expensive compared to traveling to a testing center.)
As to how to specifically estimate your proficiency level - ask the native speaker to quiz you on that level's description (note: I'm working off of Wikipedia's descriptions of the CEFRL levels here).
For example: the native speaker introduces him/her/zirself and asks you to do the same. You reply in kind. The native speaker asks you where you live - you reply. And so on. If the native speaker can follow you (and vice-versa), that's roughly A1 proficiency.
Now you move on to discussing your day at work. You talk with the native speaker about your coworkers, about lunch, about the meeting you had. If the native speaker can follow you (and vice-versa), that's roughly B1 proficiency.
Again, this is a very rough measure, but if you can find a native speaker, it's free.
In addition to @Laure's answer, DIALANG is also available on a website under the subdomain of Lancaster University's official site. The web application requires cookies, JavaScript, and popups to be enabled. Chrome is recommended.
Depending on the language you are learning, there could be training sets for the official language tests.
For German, for example, the Goethe Institut offers practice sets that are roughly equal in difficulty to the actual language test.
It might take you two hours or so to finish but afterwards you should have a good idea of how your overall language proficiency (writing, listening,...) is. Only your speaking proficiency will be hard to test without a native speaker.
The descriptions of the CEFR levels are not based on vocabulary size or grammar, but on "can-do statements". You can find a lot of information about the CEFR on the website of the Council of Europe, which developed the framework. For example, for the lowest level, A1, Global scale provides the following description:
Can understand and use familiar everyday expressions and very basic phrases aimed at the satisfaction of needs of a concrete type. Can introduce him/herself and others and can ask and answer questions about personal details such as where he/she lives, people he/she knows and things he/she has. Can interact in a simple way provided the other person talks slowly and clearly and is prepared to help.
For level C2, the highest level, the Global Scale provides the following description:
Can understand with ease virtually everything heard or read. Can summarise information from different spoken and written sources, reconstructing arguments and accounts in a coherent presentation. Can express him/herself spontaneously, very fluently and precisely, differentiating finer shades of meaning even in more complex situations.
The COE website also provides a self-assessment grid, which is available for 32 languages, including Esperanto.
For example, the self-assessemnt grid for Spanish contains can-do statements for the following aspects: comprensión auditiva (listening comprehension), comprensión de lectura (reading comprehension), interacción oral (spoken interaction), expresión oral (spoken production) and expresión escrita (writing).
For expresión escrita, the self-assessment grid says:
Soy capaz de escribir postales cortas y sencillas, por ejemple para enviar felicitaciones. Sé rellenar formularios con datos personales, por ejemplo mi nombre, mi nacionalidad y my dirección en el formulario del registro de un hotel.
So, essentially, if your target language is one of the languages for which the Council of Europe, download the corresponding self-assessment grid from the Council of Europe's website and work through it skill by skill. For each skill, not the level you reach. These self-assessment grids are in the target language they describe. If your target language is not listed, you'll have to fall back on a grid for a language you know or perhaps on sites such as Dialang (mentioned in other answers).
I am using the material from the Common European Framework of Reference but the following interpretations are mine.
The early, A1, A2, and B1 levels seem to be defined by quantity of language knowledge, and the later levels, B2, C1 and C2 by quality.
A1, A2, and B1 refer to mastery of common and everyday language. An A1 knows only a few words and phrases, typically about identifying and introducing people, time and location, weather, etc. An A2 knows "many" words and phrases, and a B1 knows "most" words and phrases in everyday, common use. A B1 is more practiced in the language and has better control of grammar than an A1 or A2, but may still have some difficulty or discomfort in getting around, even though s/he is capable of it.
The paths seem to diverge at B2, where some "expertise" is expected. One kind of B2 is a "super B1," who is more fluent and spontaneous with everyday situations, with a broader knowledge of vocabulary and grammar than a B1. The other kind of B2 is developing expert skills in a narrow field such as business, science or law (usually the profession or area of interest), even while not being fluent overall.
The paths converge again at the C1 level, where one gains the other skill (either greater overall fluency or expert knowledge). A C2 is basically a "complete" and fluent speaker of the language, with maybe slight weaknesses of accent or idiom preventing them from being a fully "native" speaker.
