How to Use Sock Blockers and a Sock Ruler: A Practical Guide
If you've ever wondered what sock blockers actually do, whether you really need one, or how you're supposed to use a sock ruler, you're not alone.
Both are simple tools designed to make sock knitting a little easier – but they do very different jobs.
A sock ruler is primarily used while you're knitting, helping you measure the length of your sock and work out when it's time to start your heel or toe. A sock blocker comes into its own once you've finished knitting, helping your socks dry to a neat, even shape after washing.
In this guide, we'll look at how to use both, including adjustable sock blockers, how to measure your socks correctly and what that mysterious negative ease actually means.
What Is a Sock Blocker?
A sock blocker is a flat, foot-shaped form that you slide a finished, damp sock onto after washing.
Blocking helps your knitting settle into shape, evens out your stitches and can make lace, colourwork and other stitch patterns look much more defined. It also makes a freshly knitted pair of socks look particularly lovely – which is handy if they're destined to be a gift.
Sock blockers are available in various materials and sizes. Traditional blockers are usually a fixed size, meaning you may need different blockers if you regularly knit socks for different-sized feet.
Adjustable sock blockers solve that problem by allowing the foot length to be changed.
How to Use Adjustable Sock Blockers
Our adjustable sock blockers have a sliding foot section which allows one blocker to accommodate a range of foot sizes.
Foot size is measured from heel to toe, but you don't need to measure the foot that your socks are intended for because our adjustable sock blockers have their own size guide...
To adjust the blocker:
- Loosen the two screws on the adjustable section. You can usually do this with a fingernail, although a screwdriver can also be used.
- Slide the adjustable section along the blocker until it lines up with the required size marking.
- Retighten both screws to secure the adjustable section.
- Repeat with the second blocker (if you have one) so that both are set to the same size. Check out our set of two adjustable sock blockers.
Once adjusted, wash or soak your finished socks according to the care instructions for your yarn and gently remove excess water.
Slide each damp sock over a blocker, taking care not to overstretch the fabric. Smooth the sock into position, making sure the heel sits correctly and the stitches aren't being pulled or distorted.
Then simply allow the socks to dry completely before removing them.
Don't Stretch Your Socks to Fit the Blocker
Blocking isn't about stretching a sock until it fits a particular size. The blocker should support the sock's natural shape rather than force it into one.
If you're having to pull hard to get the sock onto the blocker, check that you've set the blocker to the appropriate size.
What Is a Sock Ruler?
A sock ruler is a measuring tool specifically designed for sock knitting.
Unlike a normal ruler or tape measure, it can be inserted inside the sock, allowing you to measure your knitting while it's still on your needles.
That's particularly useful because knitted fabric can stretch when you lay it flat and pull a tape measure alongside it, making it surprisingly easy to get an inaccurate measurement.
Our wooden sock ruler has both centimetre and inch measurements, with each scale measured from the very bottom of the ruler. It also includes UK and European shoe-size guides to give you a useful reference when knitting socks for different foot sizes.
How to Use a Sock Ruler for Cuff-Down Socks
If you're knitting your sock from the cuff down, you'll normally use your ruler after you've completed the heel and are knitting the foot.
Insert the rounded end of the sock ruler into the sock until it sits against the back of the heel.
The ruler now lets you see how long the foot of your sock is without having to take your knitting off the needles.
Continue knitting until you've reached the point at which your pattern tells you to begin the toe decreases.
Remember that the toe itself adds length, so don't simply knit all the way to the wearer's total foot length and then start decreasing. Your pattern should tell you how much length to allow for the toe.
How to Use a Sock Ruler for Toe-Up Socks
For toe-up socks, we're doing essentially the same thing in reverse.
Insert the rounded end of the ruler into the toe so that the very bottom of the ruler sits at the end of your knitted toe.
You can then measure the foot as you work and determine when you've reached the point where you need to begin your heel.
Again, exactly when you start the heel depends on the heel construction you're using, so follow the instructions in your pattern rather than relying solely on shoe size.
What Does Negative Ease Mean in Sock Knitting?
If you look closely at our sock ruler, you'll spot the words:
Deduct 10% for negative ease.
So what does that mean?
A knitted sock generally needs to be slightly smaller than the foot it's going onto. If it were exactly the same size – or larger – it could become loose and baggy as you wear it.
This difference is known as negative ease.
For example, if a foot measures 25cm from heel to toe, deducting 10% gives:
25cm - 2.5cm = 22.5cm
So a sock with approximately 10% negative ease would have a finished foot length of around 22.5cm.
Ten percent is a useful general guide rather than an absolute rule. Yarn, gauge, stitch pattern and personal preference can all affect how much negative ease feels comfortable.
What Are the Shoe Sizes on a Sock Ruler For?
The UK and European shoe-size markings provide a handy guide to foot length and can make measuring someone's foot incredibly simple.
Ask them to place their foot directly onto the sock ruler with their heel lined up with the curved bottom edge. Look at where the end of their longest toe falls against the shoe-size guide and you'll have their approximate shoe size.
This can be particularly handy if you're knitting socks for someone else – and it's certainly easier than chasing them around with a tape measure!
The shoe-size markings are a guide, so if you're knitting a particularly close-fitting sock or following a pattern that requires precise measurements, it's always worth checking the pattern's sizing instructions too.
Sock Ruler vs Sock Blocker – What's the Difference?
It's easy to confuse the two because they're both sock-related knitting tools, but they have completely different jobs. Browse our range of sock blockers and sock rulers.
A sock ruler helps you make the sock the right size.
You use it while you're knitting to measure your progress and determine when to begin different parts of the sock.
A sock blocker helps your finished sock take shape.
You use it after you've finished knitting and washed your socks, allowing them to dry neatly and evenly.
They're useful independently, but if you knit socks regularly, having both makes the whole process considerably easier.
Do You Really Need Sock Blockers?
Strictly speaking, no.
You can knit perfectly good socks without ever owning a sock blocker. Socks can be washed, gently reshaped by hand and laid flat to dry.
But sock blockers make it much easier to achieve a consistent shape, particularly if you knit lots of socks. They're also brilliant for showing off stitch patterns and for getting a handmade pair looking their best before giving them as a gift.
Adjustable sock blockers have the additional advantage of being useful for several different foot sizes rather than requiring a separate pair of blockers for every size you knit.
Do You Need a Sock Ruler?
Again, you can certainly knit socks without one. A tape measure will do the job.
But a sock ruler makes repeated measurements considerably quicker, particularly because you can insert it directly into your knitting without removing your sock from the needles.
And when you're approaching that crucial "Is it time to start the heel yet?" or "Can I start the toe decreases?" moment, anything that saves you repeatedly attacking your knitting with a floppy tape measure is rather handy.
Made for Sock Knitters in Suffolk
Our adjustable sock blockers and wooden sock rulers are made by us here in Suffolk and were designed to make the practical side of sock knitting that little bit easier.
Whether you're knitting your first pair or you've reached the stage where there's another pair of socks on your needles, getting the measurements right means more comfortable socks – and considerably less guesswork.
And really, after spending hours knitting thousands of tiny stitches, your socks deserve to fit properly. 🧦
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