Surgeon’s Loop
Double overhand on a bight — fastest reliable fixed loop.
Beginner · Monofilament / Fluorocarbon
Connection card
Surgeon’s Loop
For line → loop (fixed end loop), loop → loop.
A bight in the standing line, overhand through the bight, loop stays open under load.
This card does not say how strong the knot is. A retention figure comes from a bench, in one material, at one diameter, tied by somebody who ties it all day — and the line in your hand is none of those. What it does tell you is whether the thing you have just tied is the thing the record describes.
What this plate is telling you
Double overhand on a bight — fastest reliable fixed loop.
Save this as a picture and it works with a dead signal and a nearly dead battery, which is when a joint is most often tied badly. The rest of this page — the steps, the seating sequence, the failure modes and the bench — is for the evening before.
Why this knot
What it earns its place with, what it costs, and what to reach for instead.
- When the absolute smallest loop knot is required
- Very fine tippet where the double-overhand bulk matters
- Doubling too little line to tie the overhand and still leave a usable loop
- Making only one pass through the overhand
- Letting the two strands of the double twist over each other inside the knot
- Trimming the tag before the knot closes, or pulling only the standing line
- Perfection LoopBeginner
A small fixed loop in the end of a leader, tippet or fly line that lies in line with the standing line
- Dropper LoopIntermediate
A fixed loop that stands out from the middle of a line or leader, as an attachment point for an extra fly or hook
- Bimini TwistAdvanced
Making a double line with a loop at the end, for loop-to-loop leader connections or as the doubled line in knots such as the Yucatan
Before you start
- ·Fold back a bight a little longer than the loop you want. The knot and the loop both come out of this doubled line.
- ·Set the loop size while the knot is still loose. It stays that size once the knot closes.
- ·Two passes make the knot. Animated Knots notes a third pass adds little and makes the knot bulkier.
- ·Easiest in mono and usable in fluorocarbon. It is a bulky loop, and other knots usually suit braid better.
Step 1 of 3 · move 1 of 1. Double the line into a long bight and choose the finished loop size
Space plays or pauses. Keys 1, 2, 3 and 4 set the speed. Arrow keys change the move.
swipe to step
01.1
Double the line into a long bight and choose the finished loop size
- Hold:
- Left hand holds both parts of the doubled line together
- Move:
- Right hand draws out a bight slightly longer than the loop you want
You should now see: A long bight with both parts lying side by side and enough length to tie the knot without stealing the loop.
Fold the end of the line back on itself to make a bight a little longer than the loop you want.
A doubled section of line with the bight at one end and the tag lying beside the standing line.
Making the bight too short. You find out in step 2, when there is not enough doubled line to tie the overhand and still leave a usable loop.
Fix: Unfold it and double more line. The spare tag is trimmed off at the end.
Why: The doubled line is tied as if it were a single strand, so both the knot and the loop come out of this length.
arrow keys work
Tying procedure — Surgeon’s Loop
Step 01 / 3
Fold the end of the line back on itself to make a bight a little longer than the loop you want.
You should now see: A doubled section of line with the bight at one end and the tag lying beside the standing line.
If it goes wrong: Making the bight too short. You find out in step 2, when there is not enough doubled line to tie the overhand and still leave a usable loop.
Fix: Unfold it and double more line. The spare tag is trimmed off at the end.
Why: The doubled line is tied as if it were a single strand, so both the knot and the loop come out of this length.
Step 1 of 3 · move 1 of 1
Double the line into a long bight and choose the finished loop size
Hold: Left hand holds both parts of the doubled line together
Move: Right hand draws out a bight slightly longer than the loop you want
You should now see: A long bight with both parts lying side by side and enough length to tie the knot without stealing the loop.
Step 02 / 3
Tie an overhand knot in the doubled line, then pass the bight through the same overhand a second time.
You should now see: A loose knot showing two turns of doubled line around each other, the bight sticking out one side and the standing line and tag out the other.
If it goes wrong: Making only one pass, or letting the two strands of the double twist over each other. You see a single crossing, or strands that swap sides inside the knot.
Fix: Back the bight out, lay the two strands flat side by side, and make both passes again.
Why: Two passes make it a surgeon's loop, a double overhand tied in doubled line. Animated Knots notes that a third pass adds little and makes the knot bulkier.
Step 2 of 3 · move 1 of 3
Tie a loose overhand in the doubled line, keeping the bight open
Hold: Left hand pinches both parts where they cross
Move: Right hand brings the whole bight round to form a loose overhand
Step 2 of 3 · move 2 of 3
Pass the entire bight through the overhand once
Hold: Left hand keeps the overhand open
Move: Right hand pushes the whole closed bight through the opening
Step 2 of 3 · move 3 of 3
Take the whole bight through the opening a second time
Hold: Left hand keeps the first pass loose and orderly
Move: Right hand carries the complete bight through the same opening again
You should now see: Two complete passes of the doubled line lie in the overhand; a single pass is not the finished knot.
Step 03 / 3
Slide the knot along the doubled line until the loop is the size you want.
You should now see: A loop of the size you need, with the loose knot sitting where you want it on the doubled line.
If it goes wrong: Leaving the loop size until after the knot starts to close. Once it tightens, the loop cannot be changed.
Fix: If the knot has started to close on a loop of the wrong size, loosen it with a fingernail and slide it before it sets.
Why: Loop size can only be changed while the knot is loose. Once it closes, the loop stays that size.
Step 3 of 3 · move 1 of 2
Set the loop size, moisten the knot, and pull both line ends evenly
Hold: Left hand holds the bight at the loop size you want
Move: Right hand works the two passes snug, then pulls the standing line and tag evenly
You should now see: A compact double overhand grips the doubled line, the two parts lie side by side, and the loop keeps the size you set.
Step 3 of 3 · move 2 of 2
Inspect the two passes and trim the tag only after a firm test pull
Hold: Left hand loads the finished loop and standing line
Move: Right hand checks both passes are present and trims excess tag if needed
You should now see: Two passes remain visible, the knot is symmetrical and closed, and the fixed loop does not change size under load.
What this is based onReframed, rope unmoved
- Record
- Reviewed 2026-08-09. 2 sources are cited for this record.
- Drawing
- Reframed so the rope is easier to see; the rope itself did not move. The earlier check was of the old framing, and nobody has tied the knot from this one. Recorded 2026-09-24.
- Known limits
- None that stop a reader following it were confirmed in the plate audit of 2026-09-24; smaller findings were not all re-checked.
- Strength
- Not established. No credible, comparable strength data exists for this knot, so no figure is shown.
Watch the tie
How to tie a Surgeon's Loop KnotTake Me Fishing · Opens on YouTubeExternal video from a creator we follow — not produced by us. Nothing on this page loads from YouTube until you follow the link.
Seating sequence — where failures are born
The step list compresses the finish. Run these phases in order, one at a time.
01 Moisten
Wet the structure before any load reaches it.
Zero. Nothing tightens yet.
02 Load
Take up slack slowly until the wraps begin to gather.
Light and even — both ends moving together.
03 Dress
Watch the wraps stack in order; stop and back off if any cross.
Hold, do not pull. Correction happens here or not at all.
04 Set
One continuous pull to full seat — no sawing, no jerks.
Firm, single direction, standing line against the terminal end.
05 Trim
Cut the tag square, leaving a short stub proud of the knot.
None. Never trim under load.
Finished structure — what correct looks like
Drawn from a rope model of this knot: which strand passes over which comes from where the rope actually lies.
- Structure
- Fixed loop from double overhand on bight
- Standing line
- Standing + loop
- Tag end
- Does not apply to this form — short depending on method
- Wraps
- Double overhand body
- Seating
- Fully seated multi-pass
Verify before you load it
Every line is pass or fail. One fail means retie — do not load a knot you argued with.
- 01Fixed loop from double overhand on bight
- 02Fully seated multi-pass
- 03Does not apply to this form — short depending on method
- 04Double overhand body
- 05Expected multi-pass form
- 06Surgeon loop
Field notes — dark, cold, gloves
- ·Retie by feel first, light second — the seat is a tactile event, not a visual one.
- ·Gloves off for the dress phase. Fabric hides a crossing wrap.
- ·Wrong twice in a row means the material or the hardware is fighting you. Change one, not your technique.
Surgeon’s Loop — finished-state checks, on the shared reference layout
When this family fails, it fails as these. The recovered end still outranks the name.
A loop that stays the size you made, with a return that cannot cinch.
- !Loop cinched around the hardware — action is dead
- !Return path reversed, so it becomes a slip loop
- !Fluoro in a lock that only behaves on mono
- !Seated on the standing line alone, leaving the tag side loose so the tag pulls back inside
- !Tag trimmed before the knot fully closed, leaving it loose
- !Strands of the double crossed over each other inside the knot
- !Loop changes size under a test pull, showing the knot has not seated
Single pass only — not a Surgeon's loop
May slip and the eye walks
Double pass is the minimum; one pass is an overhand loop · step 02
Messy multi-pass body
Weaker eye, bulk that ticks
Clean passes keep the lump compact and load-bearing · step 02
Passes not completed through the loop
Unreliable — the eye never locked
Every pass must go through the loop before the seat · step 03
Too bulky for small guides or keepers
Check
- ?Compare to Perfection Loop size
Then
- →Use Perfection Loop
- →Drop to double surgeon
Finished check failed — Single overhand only
Check
- ?Double overhand completed on the doubled line
- ?Loop size stable after draw
- ?Tags exit cleanly
Then
- →Retie. Incomplete double overhand fails as a fixed loop.
Single pass only — not a Surgeon's loop
Check
- ?May slip and the eye walks
- ?Inspect step 02
Then
- →Retie. Do not dress a defective structure and call it seated.
Messy multi-pass body
Check
- ?Weaker eye, bulk that ticks
- ?Inspect step 02
Then
- →Retie. Do not dress a defective structure and call it seated.
Passes not completed through the loop
Check
- ?Unreliable — the eye never locked
- ?Inspect step 03
Then
- →Retie. Do not dress a defective structure and call it seated.
Same failure class, different geometry. Open the plates — Diagnose still starts from the symptom.
Get it right with everything in your favour0/5 clean
Nothing logged on this knot yet, so it starts on the bottom rung.
Good light, dry hands, a table. Until the sequence is automatic here there is nothing for the harder rungs to test — you would only be learning that difficult conditions are difficult, which you already knew.
How · Tie it, check it against the list, log it. Five clean and the ladder opens.
Nothing marked. Log it clean, or mark what happened first.
Strength, and where the number comes from
Not established
No published break test, and the percentage would in any case need to say whether it is of the doubled loop or of the single line it is formed from — no source we read makes that distinction.
Percentages come from published tests on their own line, their own knot-tyer and their own pull rate. Yours is a different system. Treat a figure as a reason to test, not as a result you already have.
- Animated Knots — Surgeon’s Loop
- FishingKnots.com Knot Strength Database
Recovered from this record’s historical modelSourceId registry.
Record reviewed 2026-08-09
Vetted references
- Surgeon’s Loop
Animated Knots by Grog
- How to tie a Surgeon's Loop Knot
Take Me Fishing
Check the finished knot against what correct looks like before you load it.