Foothold Now

The SUDS scale (Subjective Units of Distress), explained

SUDS—the Subjective Units of Distress Scale—is the 0–100 rating used across exposure therapy, ERP, and much of CBT to answer one question: how intense does this feel, right now?

The scale was created by psychiatrist Joseph Wolpe, the pioneer of systematic desensitization (1958)—the first therapy built on climbing a graded hierarchy of fears. He published the scale in his 1969 book The Practice of Behavior Therapy. It has stuck around for a simple reason: distress has no lab test. The person feeling it is the only instrument available—so the scale leans into that. Zero means fully at ease; one hundred means the most distressed you can imagine being. Everything else lives in between.

The word that matters is “subjective”

Your 60 doesn’t need to match anyone else’s 60, and there is no wrong answer. What makes SUDS useful isn’t accuracy against some outside standard—it’s consistency with yourself. If the same situation that rated 70 three weeks ago now rates 40, something real has changed, and the numbers caught it. That’s the whole trick: turning a fog of “awful, I think?” into a trend line you can watch fall.

Example anchors

Most people find the scale easier with a few reference points. Picture it as a spectrum from fully at ease to the most distressed you can imagine:

calm worst imaginable 0 25 50 75 100

And these are common reference points—feel free to write your own:

0–10Calm. At ease, nothing pulling at you.
20–30Mild. Noticeable, but workable—you can carry on.
40–50Moderate. Uncomfortable; your attention keeps getting pulled toward it.
60–70Strong. Hard to focus on anything else; the urge to escape is loud.
80–90Severe. Near the edge of what feels tolerable.
100The worst distress you can imagine.

Don’t overthink precision—the nearest 5 or 10 is plenty. The number is a snapshot, not a verdict.

How SUDS powers exposure practice

SUDS ratings do two jobs in graded exposure and ERP:

  1. They order the ladder. Rating each avoided situation 0–100 turns a pile of dread into an exposure hierarchy (fear ladder)—sorted gentlest first, so you always know where to start.
  2. They make progress visible. Rating a practice before you start, at the peak, and after it ends shows the shape of the wave and, across repetitions, shows the peaks coming down. Watching a step fall from 70 to 40 to 15 is the evidence that keeps people climbing.

Two honest tips: rate what is, not what you think it should be. And a high peak isn’t failure—it usually means the exercise is working, because you stayed long enough to feel it crest and settle.

Common questions

Who invented the SUDS scale?

Psychiatrist Joseph Wolpe, the pioneer of systematic desensitization, published the Subjective Units of Distress Scale in his 1969 book The Practice of Behavior Therapy.

What SUDS level should exposure practice start at?

Around 30–40 out of 100: uncomfortable, but doable. Too easy teaches nothing; too hard teaches retreat.

Do SUDS ratings need to be exact?

No—the nearest 5 or 10 is plenty. The scale is subjective on purpose; consistency with yourself is what makes the trend meaningful.

References

Wolpe, J. (1958). Psychotherapy by reciprocal inhibition. Stanford University Press.

Wolpe, J. (1969). The practice of behavior therapy. Pergamon Press.

Foothold Now is built around SUDS. Every step on a ladder carries a 0–100 rating, every practice logs before, peak, and after, and when a step comes all the way down to zero, it settles. Free.

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