Masonry nail pilot hole bit size chart (nail size to bit)
Ask five sites what drill bit to use for a masonry nail pilot hole and you get five different answers: 3/16 or 1/4 in, or a bit slightly smaller than the nail, or the same size, or 0.5 mm smaller. No nail manufacturer publishes a gauge-to-bit table, and the bit makers publish bit lists without nail pairings, which is why every chart on this question on the search results is a paragraph of advice rather than numbers [1][7][11][12][13]. This page builds the missing table the only defensible way: manufacturer-published nail diameters on one axis, the published bit rules applied to them, and every recommendation snapped to a bit diameter that DeWALT and Hilti actually stock, so no row asks you to buy a bit that does not exist [5][6].
The four published rules, side by side
These are the only concrete bit-to-nail rules we could find published with numbers attached, and they do not agree with each other:
| Source | Rule as published | Worked example given | Sources |
|---|---|---|---|
| The Spruce | masonry bit the same diameter as, or slightly smaller than, the nail | none; stated as a selection rule for pilot holes [13] | [13] |
| Hometosight | bit 1/32 to 1/16 in (0.8 to 1.6 mm) smaller than the nail diameter | oversized-hole mistake table prints the 1/32 to 1/16 band [11] | [11] |
| Qinjia (nail maker) | bit diameter 0.5 mm smaller than the nail shank | 4.5 mm bit for a 5 mm nail [2] | [2] |
| Shuntool | bit slightly smaller; article tables print two exact pairs | 1/8 in bit for a 3/16 in nail; 3/16 in bit for 1/4 in nails; one article also says about 1/16 in narrower [12][7] | [7][12] |
| DFS (nail maker) | fixed spec, not a rule: 3/16 in pilot hole for its whole fluted concrete nail line, all lengths | 3/16 in drill size printed in the product table and the application spec [1] | [1] |
Two of those rules come from nail manufacturers themselves (Qinjia, DFS), which outranks the how-to consensus on our source ladder. The tightest published rule, Qinjia's 0.5 mm under, and the loosest, The Spruce's same-or-slightly-smaller, can point at different bits for the same nail, and that disagreement is the honest headline of this chart. Where they diverge, the tables below print both rather than averaging them away.
What the nail makers actually publish
The chart needs real shank diameters first. For dedicated masonry and concrete nails, two makers publish full numbers. Ramset lists shank diameters of 2.4, 3.2, 3.6, 3.8, 4.0 and 4.2 mm for its hand-driven concrete nails, in lengths from 15 to 100 mm, rated for medium-strength concrete and solid block [3]. Diversified Fastening Systems sells the inch-world equivalent, fluted concrete nails from 1-1/2 to 4 in long, and specifies the same 3/16 in pilot hole for every length, with 1 in minimum embedment and a 2 lb hammer [1]. McMaster-Carr's catalog table gives the shank diameters behind that class: 0.13, 0.16, 0.19 and 0.25 in fluted nails for masonry [9]. Hilti's 4 mm X-U P8 exists on the powder-actuated side, where no pilot hole is drilled at all [4].
For the framing nails people actually try to drive into brick and concrete walls (the 8d to 16d question), the diameters are structural spec, published identically by two connector manufacturers: Simpson Strong-Tie, printing the AWC/NDS Table L4 values (6d 0.113, 8d 0.131, 10d and 12d 0.148, 16d 0.162, 20d 0.192 in), and MiTek, whose fastener catalog prints the same 0.131, 0.148, 0.162 and 0.192 in shanks for its 8d through 20d commons [8][10]. Maze Nails publishes the gauge-to-decimal lookup that ties penny talk to thickness: 11 ga is 0.1205 in, 10 ga is 0.135, 9 ga is 0.1483 [14]. Penny size alone never gives you diameter: a 16d common is 0.162 in but a 16d box nail is 0.135 and a 16d sinker 0.148, per the same NDS table [8], so the chart rows below say common nails or they say nothing.
The chart: masonry nail to pilot bit
How to read it. The shank column is manufacturer-published. The rule-matched bit column applies the two published nail-maker rules, Qinjia's 0.5 mm under and the how-to band of same-size down to 1/16 in under, and then snaps to the nearest bit that DeWALT or Hilti actually catalogs: the DeWALT percussion line runs 1/8, 5/32, 3/16, 1/4 in and up in 3-flat shank [6], and Hilti's SDS-plus TE-C ladder starts at 5/32 in [5]. The under-size column is the measured gap, nail minus bit; positive means the bit is smaller than the nail. Where the two published rules land on different bits, both are printed.
| Nail | Shank dia | Qinjia rule (0.5 mm under) | How-to band (0 to 1.6 mm under) | Stocked bit to buy | Under-size | Sources |
|---|---|---|---|---|---|---|
| Ramset concrete nail | 2.4 mm (0.094 in) | 1.9 mm, not stocked in the inch ladder | no stocked bit at or under this shank | none: direct drive per Ramset (interference fit) | n/a | [3][2] |
| Ramset concrete nail | 3.2 mm (0.126 in) | 2.7 mm, not stocked | 1/8 in (3.2 mm), same size | 1/8 in, flagged: equals the shank, Spruce-rule only | 0.0 mm | [3][13] |
| Ramset concrete nail | 3.6 mm (0.142 in) | 3.1 mm, not stocked | 1/8 in (3.2 mm), 0.4 mm under | 1/8 in | 0.4 mm | [3][11] |
| Ramset concrete nail | 3.8 mm (0.150 in) | 3.3 mm, not stocked | 1/8 in, 0.6 mm under | 1/8 in | 0.6 mm | [3][11] |
| Ramset / Hilti-class nail | 4.0 mm (0.157 in) | 3.5 mm, not stocked | 5/32 in (4.0 mm), same size | 5/32 in, flagged: equals the shank; 1/8 in is 0.8 mm under if the wall is old or thin | 0.0 mm | [3][4][13] |
| Ramset concrete nail | 4.2 mm (0.165 in) | 3.7 mm, not stocked | 5/32 in, 0.2 mm under | 5/32 in | 0.2 mm | [3][13] |
| Fluted concrete nail | 0.13 in (3.3 mm) | 2.8 mm, not stocked | 1/8 in, 0.1 mm under | 1/8 in, or 3/16 in per the DFS fixed spec | 0.1 mm | [9][1][13] |
| Fluted concrete nail | 0.16 in (4.1 mm) | 3.6 mm, not stocked | 5/32 in, 0.1 mm under | 5/32 in, or 3/16 in per the DFS fixed spec | 0.1 mm | [9][1][13] |
| Fluted concrete nail | 0.19 in (4.8 mm) | 4.3 mm, not stocked | 3/16 in (4.8 mm), same size | 3/16 in (matches the DFS 3/16 in spec) | 0.1 mm | [9][1] |
| Fluted concrete nail | 0.25 in (6.35 mm) | 5.85 mm, not stocked | 3/16 in, 1.6 mm under (top of band) | 3/16 in (Shuntool's published 1/4-to-3/16 pair) or 1/4 in, same-size per Spruce | 1.6 mm | [9][7][13] |
Honest gaps in that table, printed rather than papered over. The Qinjia 0.5 mm-under rule outputs metric bit sizes (1.9, 2.7, 3.1, 3.3, 3.5, 3.7 mm) that no US bit maker catalogs in the inch percussion ladder; if you buy metric masonry bits, those are the sizes to match. The 2.4 mm Ramset nail has no pilot-bit answer at all in any published source: Ramset designs it for direct hammer driving, and no bit smaller than 1/8 in is stocked by the makers surveyed here. And the DFS 3/16 in spec is a fixed value published for DFS nails whose own diameters DFS does not print; pairing it with the McMaster 0.13 to 0.25 in fluted diameters is our inference, labeled as such, not a DFS claim.
Framing nails into masonry: the 8d to 20d question
This is the query class with the worst advice on it: people ask about a 16d into a brick wall or basement slab, and the answers mix masonry nail guidance with framing nail sizes. Framing commons are not masonry nails (they will bend in poured concrete however you drill it, The Spruce's high-grade hardened steel distinction [13]), but in brick, mortar, and block, pilots plus a hardened nail are a real light-duty technique, so here are the numbers on the same basis as the chart above. Diameters are the NDS values as printed by Simpson Strong-Tie and MiTek [8][10]:
| Common nail | Shank dia | How-to band bit | Stocked bit to buy | Under-size | Sources |
|---|---|---|---|---|---|
| 6d common | 0.113 in (2.9 mm) | same-or-smaller only; nothing stocked is this small | 1/8 in (3.2 mm) is oversize; no inch pilot bit exists under this shank | n/a | [8][6] |
| 8d common | 0.131 in (3.3 mm) | 1/8 in, 0.1 mm under | 1/8 in | 0.1 mm | [8][10][13] |
| 10d / 12d common | 0.148 in (3.8 mm) | 1/8 in, 0.6 mm under, or 5/32 in same size | 1/8 in | 0.6 mm | [8][10][11] |
| 16d common | 0.162 in (4.1 mm) | 5/32 in, 0.1 mm under, or 3/16 in same size | 5/32 in | 0.1 mm | [8][10][13] |
| 20d common | 0.192 in (4.9 mm) | 3/16 in, 0.1 mm under, or 1/4 in, 1.5 mm under | 3/16 in | 0.1 mm | [8][10][11] |
The one piece of published advice that fails this table is the 1/4 in bit recommended alongside 16d nails in a widely-circulated Family Handyman comment thread: a 1/4 in hole is 2.2 mm larger than a 16d common shank, nearly 9 percent, and the nail cannot grip it. That recommendation probably descends from advice for powder-actuated fasteners or from the DFS-style 3/16-plus-clearance habit; against published diameters it is simply wrong for 16d [8]. The correct tight answer, 5/32 in, is one gauge step down in the DeWALT and Hilti ladders [5][6].
Which rule wins, and when
Tight versus loose is a real trade, not one right answer. The tight rules (Qinjia 0.5 mm under, Shuntool's pairs at 1.59 mm under) maximize grip because the nail has to wedge into material rather than rattle in a tube; the loose Spruce rule (same or slightly smaller) drills faster, survives slightly worn bits, and matters most in hard old concrete where an undersize hole risks cracking the wall around it, the exact failure mode Hometosight's too-small-bit warning describes [11]. Our synthesis, labeled as ours: buy the largest stocked bit that is still clearly under the shank, 0.1 to 0.6 mm for hard poured concrete where grip matters, and step one full bit size down (0.6 to 1.6 mm under) in brick, block, mortar joints, or any wall you are afraid of cracking, which is where the how-to band's 1/32 to 1/16 in under comes from [11]. The material split is the one dimension the sources genuinely support: DFS rates its nails and 3/16 in pilots for poured concrete, block and brick [1], Ramset rates the small mm ladder for medium-strength concrete and solid block only [3], and no source publishes a separate bit table by wall material, so this page does not invent one.
Depth, hammer, and the no-pilot cases
- Depth. Qinjia says drill 5 to 10 mm deeper than the nail length so dust escapes and the nail seats flush; Shuntool and Hometosight say 1/4 in deeper; DFS sets minimum embedment at 1 in. All four are compatible: drill nail length plus 1/4 in, and never embed less than 1 in [2][7][11][1].
- Tool. Hammer drill with a carbide bit; Qinjia adds under 800 RPM in hammer mode with light pressure and water-cooling pauses, and notes only SDS-plus rotary hammers should be used for this work with their nails [2]. The drill side of that decision is our best drills for concrete page.
- No-pilot case one: powder-actuated. The Hilti X-U P8 (4 mm shank) is a ballistic-point nail fired from a DX tool into concrete 80 mm or thicker, no pilot hole, and The Spruce states pre-drilling is not required for powder-actuated nailers [4][13].
- No-pilot case two: small interference-fit nails. Ramset's 2.4 to 4.2 mm concrete nails are specified for direct hand hammer driving, anchoring by interference fit, into medium-strength concrete and solid block [3]. If your wall is harder than that, move up to the pilot-plus-fluted-nail method rather than pre-drilling for these.
- Wall thickness. Concrete should be at least three times the fastener penetration depth [13]; on the powder side Hilti publishes 80 mm minimum concrete thickness outright [4].
The SDS note
Pilot diameters for nails live at the small end of the masonry bit world, and that is where the shank-type split falls. Below 3/16 in, the stocked bits are 3-flat-shank percussion bits for a hammer drill's ordinary chuck: DeWALT's DW5221B25 (1/8 x 3 in) and DW5227B25 (5/32 x 4 in) are the two that matter for nails [6]. The SDS-plus world starts at 5/32 in in Hilti's TE-C imperial ladder and 3/16 in in most sets [5][6], so an SDS-only owner can pilot for 4 mm-class and larger nails but not for the small Ramset ladder. If you are drilling many holes, the full shank-type and diameter runs are on our masonry bit size chart, and the material-by-material bit selection logic is on drill bits by material.
What this chart is not
Three neighboring questions get their own pages. Screws and anchors into concrete follow the opposite logic (Tapcons take a bit one size smaller than the screw; wedge and sleeve anchors take the same size), and that table with embedments is the concrete anchor bit size chart. Wood-side pilot holes for screws are sized to the screw's root diameter, not its outside, on the pilot hole chart. And if the question is which bit type survives your wall rather than which diameter, that is drill bits by material. None of those pages carries the nail-gauge mapping, because until now nobody published one.
Sources
- Diversified Fastening Systems, Concrete Nails product page (pulled live 2026-09-23): fluted concrete nails 1-1/2 to 4 in, drill size 3/16 in for every length, application spec predrill a 3/16 in pilot hole through object and into concrete, 2 lb hammer, minimum embedment 1 in, substrates poured concrete, block, brick: dfsusa.com
- Qinjia (hbqinjia.com), How to Put a Nail in a Concrete Wall (pulled live 2026-09-23): match the bit diameter 0.5 mm smaller than the nail shank; worked example 4.5 mm bit for a 5 mm nail; pilot 5 to 10 mm deeper than nail length; SDS-plus hammer drill under 800 RPM: hbqinjia.com
- Ramset Australia, Concrete Nails product page (pulled live 2026-09-23): shank diameters 2.4, 3.2, 3.6, 3.8, 4.0, 4.2 mm; anchor lengths 15 to 100 mm; hand hammer driving into medium strength concrete and solid block; anchoring method interference fit: ramset.com.au
- Hilti, X-U P8 concrete and steel nails product page (pulled live 2026-09-23): 4 mm shank, ballistic point, powder-actuated DX tools, minimum concrete thickness 80 mm, no pilot hole: hilti.co.uk
- Hilti USA, TE-C (SDS Plus) imperial hammer drill bit page (pulled live 2026-09-23): stocked diameter ladder 5/32, 3/16, 1/4, 5/16, 3/8 in and up: hilti.com
- DeWALT percussion masonry bit line (pulled live 2026-09-23): DW5204 4-piece set 3/16, 1/4, 5/16, 3/8 in; specification sheet listing DW5221B25 1/8 in, DW5227B25 5/32 in, DW5222B25 and DW5223B25 3/16 in, DW5224B25 and DW5225B25 1/4 in; DW5207 7-piece set: dewalt.com, spec sheet PDF
- Shuntool, How to Pound a Nail into Concrete (pulled live 2026-09-23): drill bit size 1/8 in for a 3/16 in nail; typical bit 1/8 to 3/16 in for standard nails, 3/16 to 1/4 in for masonry nails; depth 1/4 in deeper: shuntool.com
- Simpson Strong-Tie, Fastener Overview: Nails technical note (pulled live 2026-09-23): construction nail dimensions per AWC/NDS Table L4; common diameters 6d 0.113, 8d 0.131, 10d 0.148, 12d 0.148, 16d 0.162, 20d 0.192 in; box and sinker differ at same penny size: strongtie.com
- McMaster-Carr, Concrete Nails catalog page (pulled live 2026-09-23): fluted masonry nails with shank diameters 0.13, 0.16, 0.19, 0.25 in and lengths 3/4 to 2-1/2 in. Retailer table, the only published diameter set located for inch fluted concrete nails; flagged as retailer-rank on our source ladder: mcmaster.com
- MiTek USP Product Catalog, Fasteners section PDF (pulled live 2026-09-23): nail specification table printing 8d common 0.131 x 2-1/2, 10d common 0.148 x 3, 12d common 0.148 x 3-1/4, 16d common 0.162 x 3-1/2, 20d common 0.192 x 4: mitek-us.com
- Hometosight, How to Nail into Concrete (pulled live 2026-09-23): use a bit 1/32 to 1/16 in smaller than nail diameter; oversized pilot hole means the nail has no material to grip; drill at least 1/4 in deeper than nail length: hometosight.com
- Shuntool, How Do You Put Nails into Concrete (pulled live 2026-09-23): drill bit 3/16 in for 1/4 in nails; carbide bit approximately 1/16 in narrower than the nail; hole 1/4 in deeper than nail length: shuntool.com
- The Spruce, How to Drive Nails Into Concrete by Hand (pulled live 2026-09-23): masonry bit the same diameter as or slightly smaller than the nails; pilot holes must be made in the concrete for hand-driven nails; pre-drilling not required for powder-actuated nailers; concrete at least three times the fastener penetration: thespruce.com
- Maze Nails, Nail Info reference page (pulled live 2026-09-23): nail gauge to decimal equivalents, 11 ga 0.1205 in, 10 ga 0.135 in, 9 ga 0.1483 in, plus penny-to-length equivalents: mazenails.com