Construction drawing review, in the browser
Every drawing. Every revision. One connected workspace.
Review, measure, compare and coordinate construction drawings in one browser-based workspace.
- Nothing to install — Chrome, Edge, Safari and Firefox on Windows, Mac, Linux and tablets.
- The free compare tool runs in your browser; your drawings are never uploaded.
- Subject
- Clash — door swing
- Status
- Open
- Assigned to
- Rahul Mehta
- Layer
- Review
- Line
- 2 pt · cloud
Rack moves to the north wall in Rev C — confirm against M-101.
| Subject | Status | Assigned to | Measurement |
|---|---|---|---|
| Door swing clashes with rack | Open | R. Mehta | — |
| Confirm door width (36" min) | Answered | A. Moreno | — |
| Flooring — VCT · EXAM 103 | Accepted | — | 140.0 sq ft |
Illustrated view of the workspace — drawn from the product's layout and tools, not a screenshot.
Try it here
Four jobs that usually need four tools. Try each one on this sheet.
Review, takeoff, revision compare and field coordination on one sample sheet, in your browser. Pick a job, follow the one-line instruction and draw. Nothing is uploaded or stored.
Drag a box around the door of EXAM 104 — top row, fourth room.
More tools — callouts, lengths, counts, zoom and a guided tour — in the full demo
01Review
Review on the sheet, not in an email chain.
Clouds, callouts, text, stamps and measurements, saved as you draw them. Every markup carries a status from your project's own status set, an assignee and a reply thread — so a review closes instead of trailing off.
- A Markups List you can sort, filter and save views of, with totals for measurements
- Live review sessions: see who is on which sheet and watch markups appear as they are made
- Import the comments already in your PDFs; export standard PDFs other viewers can open
| Subject | Status | Assigned to | Sheet |
|---|---|---|---|
| Door swing clashes with rack | Open | R. Mehta | A-101 |
| Confirm door width (36" min) | Answered | A. Moreno | A-101 |
| Verify beam depth at grid C | Open | Structural | S-201 |
| Finish schedule — room 105 | Accepted | — | A-601 |
@Rahul Mehta the rack moves to the north wall in Rev C — can you confirm against M-101?
Confirmed. Clearance is 920 mm with the door open. Marking it Accepted.
02Measure
Measure once. Quantities follow the drawing.
Calibrate a sheet from a known dimension, then measure lengths, areas, volumes and counts. A measurement is never stored as a number — it is the geometry times the sheet's scale — so fixing a wrong scale updates every quantity on that sheet.
- Room fill: click inside a room and its outline becomes an area
- Symbol search: box one symbol, then find and count every one like it
- Unit costs, formula columns and assemblies, with an Excel export of the priced takeoff
- Scale Calibrated from a 22'-0" grid bay 1/8" = 1'-0"
- Geometry Area polygon in WAITING 114, room fill 440.0 sq ft
- Quantity Flooring — LVT · 2 rooms, grouped by subject 700.0 sq ft
- Cost × $5.20 / sq ft · formula column · Excel export $3,640.00
Change the scale and every row recalculates — nothing is retyped.
03Compare
Find every change, not just the clouded ones.
A cloud marks what the author meant to change, not everything that did. Compare any sheet with an older version or another document — removed linework in red, added in blue, shifted or re-plotted sheets aligned automatically — and compare whole sets at once, sheet number by sheet number.
- Cloud every change in one step; the clouds are ordinary markups you can assign and resolve
- Overlay architectural, structural and MEP sheets in colour to find clashes
- Drawing checks: the sheet index, broken references, tags missing from schedules, moved grids
- A-101First floor plan3 changes
- A-102Second floor planNo change
- A-201Elevations1 change
- M-101HVAC planNew sheet
- S-201Framing planNot in Rev C
- A-601 is in the sheet index but not in the set
- Door tag D114 is not in the door schedule
- "SEE M-102" — no such sheet
04Coordinate
Punch items and RFIs, pinned where the problem is.
Pin a punch item, RFI or submittal to the spot on the drawing, add photos, assign it to a person or a trade group and track it to closed. Items made without signal on site are kept on the device and sent when the connection returns.
- Punch, RFI and submittal workflows with their own numbering, due dates and history
- Daily reports with crews, weather, work done and photos — including 360° photos
- Closeout package: drawings, closed items and daily reports in one indexed PDF
- Mon 09:14Opened on site by Ana Moreno — offline, synced at 11:02
- Mon 11:05Assigned to Drywall crew · due Fri 17 Oct
- Wed 15:40Photo added · status → In progress
- —Closed · appears in the closeout package
Feature spotlight
Revision compare, up close
Drag across the sheet. On the left, Rev B as issued; on the right, the comparison with Rev C: red linework was removed, blue was added, grey is unchanged. The free compare tool on this site shows the same colours.
Shifted or re-plotted sheets are aligned automatically before comparing. One click clouds every change, and the clouds stay on the sheet as ordinary markups.
A measurement and its quantity
The area on the sheet and the row in the Markups List are the same thing. Move a vertex and the number moves with it; add a unit cost and the cost follows.
An issue, pinned to the drawing
A punch item lives on the sheet it is about, with a status, an assignee and a due date. Open it from the pin or from the list; either way it is the same item.
Access and control
Your drawings, under your control
The access controls a project team and its IT department expect, and standard files on the way out, so your work is never locked in.
- Self-hosting on your own servers is available on the Enterprise plan.
- This website sets no cookies and makes no third-party requests; the free compare tool never uploads your files.
- Security questions? Write to hello@example.com.
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Roles
Owners, admins, members and read-only viewers. Viewers open drawings, markups and lists without changing anything.
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Restricted projects and folders
Limit a project to named people and a folder to a group; everyone else does not see it.
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Audit log
Who uploaded, exported, shared or changed access, and when — append-only, kept per organisation.
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Single sign-on
OpenID Connect with your identity provider, applied only to email domains your organisation has verified.
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Session guests
People outside your organisation can join a live review session; they see only its documents, only while it is open.
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Standard files, no lock-in
Exports are standard PDFs with real annotations; markups and quantities export to CSV and Excel.
Pricing and access
Start free. Pay per editor when you grow.
Every plan has every tool. Editors — the people who mark up, measure and manage items — are the paid seats; viewers open drawings, markups and lists without changing anything.
No account needed
Compare two drawings, free
Pick two revisions of a PDF sheet and see what changed, in your browser. Nothing is uploaded and nothing is kept after you close the page.
- Removed in red, added in blue, unchanged in grey
- Download the result as an image for an RFI or a transmittal
- Any PDF drawing, any size
Early access
The full workspace, set up by request
We are onboarding teams in early access. Tell us about your projects and we will set up your organisation.
- Free plan: 3 editors and 10 viewers, 3 projects, 2 gb of storage — every drawing and field tool, no time limit
- New organisations get 14 days of the Business plan
- Team and Business plans are priced per editor; viewers are free
- Enterprise: custom limits, invoice billing and self-hosting on your own servers
Already have an account? Sign in. Questions about plans: hello@example.com.
Questions
Straight answers
What the product does today, in plain words. If your question is not here, write to us.
What is Planspector?
Planspector is a browser-based workspace for construction drawings: PDF markup and review, quantity takeoff, revision compare and overlays, drawing checks, and punch lists, RFIs and submittals pinned to the drawings. It is built for contractors, subcontractors, designers and the clients and consultants who review with them.
Can I review PDF construction drawings in a browser?
Yes. Open a sheet in Chrome, Edge, Safari or Firefox on Windows, Mac, Linux or a tablet and mark it up with clouds, callouts, text, arrows, shapes, highlights, stamps and measurements. There is nothing to install; on a phone or tablet you can install it from the browser like an app.
Can I compare drawing revisions?
Yes. In the app you compare any sheet with an older version or another document — removed linework in red, added in blue — with automatic alignment of shifted sheets, whole-set comparison by sheet number and clouded changes. The free compare tool on this site compares two PDF pages in your browser without an account.
Does the platform support quantity takeoff?
Yes. Calibrate a sheet from a known dimension, then measure length, area, perimeter, volume, count, angle, radius and arc length. Room fill measures a room with one click and symbol search counts every instance of a symbol. Add unit costs and formula columns, group quantities by room and export the takeoff to Excel.
How do I get started?
Try the free compare tool right now, or request early access and we will set up your organisation. The Free plan has 3 editors, 10 viewers, 3 projects and 2 GB of storage with every tool and no time limit, and new organisations get 14 days of the Business plan.
What access options are available?
Organisation roles are owner, admin, member and viewer (read-only). Projects can be restricted to named people and folders limited to groups. People outside your organisation can be invited to a live review session and see only its documents while it is open. Single sign-on with OpenID Connect is available on the Business plan.
Does it work without a connection on site?
Drawings you have opened stay available, and markups, punch items and other field items made without signal are kept on the device and sent when the connection returns.
Can I bring the markups I already have?
Yes. Comments made in other PDF tools are imported as editable markups, and exports are standard PDFs that other PDF viewers can open and edit.
Bring your next drawing set.
We are onboarding teams in early access. Tell us about your projects and we will set you up — or compare two drawings in your browser right now, no account needed.