There are many ways of assessing your level of sewing ability.
These are ones I feel comfortable with.

It’s easy to know when you’re a total beginner 😀
At Complete Beginner level your first need is learning how to use your sewing machine, see machine posts 1 and 2.

Further levels can be bit vague to define.
At Comfortable Beginner level you can start to make items, as you know how to use a machine, cut out, sew seams and hems. See First projects.

Can you claim to be at Advanced Beginner level ?
I suggest you can count yourself as an Advanced Beginner if you can make the most basic of casual garment capsules, including :
– elastic-waist pants or skirt,
– a cut-on sleeve (or possibly flat set sleeve) top or dress,
– a jacket without front closure, such as a kimono/robe.

Here is a post on elastic waist pants,
there are three posts in the cut-on sleeve tops series,
and a post on robe/ kimono patterns.

You might like to be guided by the instructions with these patterns :
100 Acts of Sewing. Sonya Philip has Creative Bug video classes for most of her patterns (pdf pattern included), and there are full size patterns and written instructions in her book The Act of Sewing.
Or try All Well Workshop or Tropical Research.

You can clothe yourself with these skills, so there’s no need to learn more 😀

If you are beginning to feel confident about sewing darts, buttonholes, zippers, using knits/ slippery/ thick fabrics, or doing pattern matching or fussy cutting, and improving the fit of your makes, you are moving into Intermediate skills.
Posts about some of these skills on this blog. The Technique tabs above the photo here are in alphabetic order.

What would justify you in claiming to be at Upper Intermediate level of sewing ability ?
Perhaps you can make shirts, fly-front pants, and lined blazers (here are some examples of on-line classes), or a closely fitted dress. But I think to claim this level you need to have the skills to make pretty well any pattern that is put in front of you.

I like the following criteria, originally posted by CCL at Stitcher’s Guild (which is sadly no longer available) – posted here with permission.

A contest was suggested at SG in which people could enter at 2 levels of ability :
– Beginner to Intermediate,
– Intermediate to Advanced,
and the question was – how do I know what is my level of ability ?

CCL’s reply :

I have looked at a lot of skill level determinations and don’t like any of them that are based on years.  I was thinking of something like this. . .
the idea being that if you can check off all five of the major bullets below, then you can self-define as Intermediate to Advanced and enter in that category. 
If you cannot check off all five, then you can self-define as Beginner to Intermediate. 

Made over 50 garments

Made more than 3 of the following types of garments:
◦ Jacket
◦ Shirt with stand and front band
◦ Coat
◦ Fitted dress
◦ Pants with fly front zipper
◦ Lined garment

Sewn garments out of more than 3 of the following fabrics:
◦ Lace
◦ Leather or faux suede
◦ Chiffon
◦ Silk Dupioni
◦ Boucle
◦ Wool coating
◦ Fake or real fur
◦ Taffeta
◦ Satin

Successfully used more than 4 of the following techniques:
◦ Invisible zipper
◦ Hong Kong seams
◦ Welt pockets
◦ Underlining
◦ Bias binding for neck or armhole finish
◦ Set in sleeves
◦ Bound or hand made buttonholes
◦ Calculated for turn of the cloth

Used at least 3 of the following hand stitches:
◦ Slip stitch
◦ Back stitch
◦ Catch stitch
◦ Pad stitch
◦ Whip stitch
◦ Blanket stitch

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Me – I realise I have not been very adventurous in my use of fabrics !
Knits don’t appear in CCL’s list. There are many different types, which vary in difficulty. I think the easiest knits come at the dividing line between Beginner and Intermediate.
Outerwear protective gear fabrics are another category which might be included.
I don’t write posts on fabrics as I just look at Sandra Betzina’s Fabric Savvy.

Most of the posts on this Aim for Quality site are about beginner to lower Intermediate skills.

At Advanced level ?

Advanced level doesn’t necessarily involve more complex techniques.
It is usually demonstrated by making tailored garments or spectacular special occasion gowns. Though those can be difficult criteria to define, as there are quite easy patterns for both.
What Advanced level does emphasise is having everything – all materials, all techniques, every stitch, the fit – of the highest quality.

If you dream of going to this level, have a look at the Haute Couture Club of Chicago’s Fashion Shows with runway photos.
The club started with a ‘must have made a notched-collar jacket’ membership requirement, but has discontinued that ! See the post on Intermediate Classics : perhaps the Club discontinued the notched-collar requirement because it can be fulfilled at many levels of difficulty.

For inspiration, or reminders that top designers may go way outside anything wearable in real life, there are photos of all the top professional designer runway shows at Vogue.com

There are two easy-access teachers who aim to teach ‘couture’ sewing :
patterns from Claire Shaeffer,
and videos from Susan Khalje.
There are of course local big-city couture teachers who are just as good but not internationally known.

It is said that to get to a top level of skill (as in playing a musical instrument) you have to practise for 10,000 hours. That works out as 2 hours a day for over 13 years, including gradually increasing the difficulty of what you are working on. How many hours of graded difficulty sewing have you put in so far 😀
Of course you can stop learning when you get to a level of ability you enjoy (as most amateur musicians do). Our sewing hours are spent on a hobby so should be fun, they needn’t be spent on getting good enough to be a couture professional !

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For those who are just interested in me-made basic clothes for themselves – you can make an attractive casual basic wardrobe if you have Advanced Beginner skills. If you have Intermediate skills, you can have a go at making most garments you might want to wear.

There’s no need to go to Upper Intermediate or Advanced levels unless you want to. Do you want to ? Would you love to have couture-standard clothes to wear ? Do you love to learn ever more difficult techniques ?
I oscillate between the relaxation of making the easiest possible garments, and dreaming of couture ! (for my actual makes I stay with easy 😀 )
The previous section has interesting and inspiring reminders of what would be involved and can be achieved 😀

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