Review revisions side by side
See the previous and updated drawings together so you can review each change in context.
The Fastest Way to Redline Mechanical PDFs
PDF Engineer is engineering drawing redline software built for mechanical teams that turn complex hardware into reality. Review, redline, and compare revisions of mechanical drawings faster with purpose-built mechanical markup tools, all while your drawings stay securely on your machine.
30 days to test on your own drawingsNo credit card required
Product Demo
Native Mechanical Symbols
BOM balloons, flag notes, dimensions, weld symbols, centerlines, and arrows for clear drawing annotations.
GD&T That Feels Right
Create clean feature control frames with proper formatting and scale-aware placement.
Drawing Revision Comparison
Compare drawings side by side, see highlighted changes, and review added, removed, or replaced text.
Screenshot Markup
Paste an image or screenshot, mark it up with the same tools, and send quick feedback without building a full PDF.
Drawing Comparison
A new revision. A clear view of what changed.
Compare revisions of engineering drawings side by side in PDF Engineer. See highlighted differences and a list of added, removed, and replaced text, so you can focus your review on the changes that matter.
See what changed
Highlighted differences help you spot revised dimensions, updated notes, and added or removed text.
Work through the differences
Use the comparison list to review changes as you check an ECO, supplier update, or new drawing revision.
Features
Stop Using Generic PDF Tools for Engineering Work
Most PDF editors were built for contracts and legal documents. Mechanical drawing reviews are different.
You need precision, speed, clean symbols, and output that looks right in front of design, quality, and manufacturing teams.
PDF Engineer removes the friction between finding a problem in a drawing and marking it clearly.
Drawing Utilities That Matter
Combine PDFs, rotate pages, zoom smoothly, and export clean redlined files ready for release.
Precision Placement
Place symbols exactly where you intend with clean alignment, consistent sizing, and professional-looking output.
Clean Output, Anywhere
Save a standard PDF that opens in Acrobat, Bluebeam, or the document viewers used in your PLM workflow.
Engineering Drawing Redline Software Built for Mechanical Teams
PDF Engineer brings mechanical drawing markup and manufacturing drawing review into one focused workflow. Use PDF redline software built around technical drawings to capture feedback and prepare clear release packages.
Mechanical teams use this drawing review software to redline engineering drawings for DFM feedback, ECO and ECR changes, supplier clarifications, and inspection notes. Engineering PDF markup tools include GD&T feature control frames, dimensions, BOM balloons, flag notes, weld symbols, centerlines, arrows, and drawing annotations, with standard PDF export.
For design reviews
Compare drawing revisions to see what changed, then capture clear feedback with consistent engineering annotations.
For manufacturing feedback
Mark tolerance issues, assembly concerns, and producibility questions directly on the PDF package your team already shares.
For supplier communication
Create clear clarification packages with standard PDFs that vendors can open without needing your internal engineering stack.
Security
Redline Engineering Drawings Without Uploading Them
PDF Engineer processes all drawings locally on your workstation. Engineering documents are never uploaded to external servers for rendering, markup creation, review, or export.
Internet connectivity supports account management, company seat administration, subscription validation, software updates, and support requests. Your drawings are processed on your machine, not in the cloud.
Local workstation processing
Rendering, markup creation, review, and export happen on your machine.
No drawing uploads
Engineering documents are not uploaded to PDF Engineer servers for document work.
Limited internet use
Connectivity supports account management, subscriptions, and updates.
Comparison
Why Not Just Use Acrobat?
If your work lives in engineering drawings, your redline tool should too.
Generic PDF Editors
PDF Engineer
Generic shapes & text boxes
Native BOM, GD&T, flag notes
Multi-step symbol formatting
One-click mechanical tools
UI built for documents
UI built for drawings
Cluttered, bloated menus
Focused, fast workflow
Image Markup
Not just for PDFs. Paste a screenshot and mark it up.
When feedback starts as a CAD screenshot, inspection photo, shop-floor image, or clipped drawing detail, paste it into PDF Engineer and use the same leaders, notes, symbols, and callouts you use on PDFs.
No conversion step
Same markup tools
Fast visual feedback
CAD screenshots
Mark a detail from a model or drawing view before someone exports a formal PDF package.
Inspection photos
Call out a tolerance issue, fit concern, or measured feature directly on the image at hand.
Clipped drawing details
Paste the small part of a drawing that needs attention and send a focused redline quickly.
Complex hardware
Built for teams that build complex hardware.
From first design review to released manufacturing drawing, PDF Engineer helps mechanical, manufacturing, quality, and supplier teams communicate changes clearly.
One drawing. Every review team.
Design Engineering
Review dimensions, tolerances, GD&T, assembly details, and manufacturability before release.
Manufacturing Engineering
Capture producibility issues, shop-floor feedback, and assembly concerns directly on the drawing.
Quality & Inspection
Document tolerance issues, nonconformances, inspection findings, and required drawing changes.
Supplier Collaboration
Send clear, standard PDF redlines without requiring suppliers to adopt another proprietary review platform.
ROI calculator
Estimate the cost of slow drawing reviews
See how much engineering time and labor cost your team could recover with a faster redlining workflow.
Step 1
Your drawing-review team
Labor baseline
$
Step 2
Your expected efficiency gain
Not sure? Start with 20%.
20%
5%50%
This is an estimate only. PDF Engineer does not guarantee a specific savings percentage.
Step 3
PDF Engineer cost
$
Defaults to the current annual plan price.
Advanced assumptions
PDF Engineer ROI Estimate
$18,277
Estimated annual net savings
288
hours reclaimed each year
1,015%
estimated first-year ROI
1.1 months
estimated payback period
0.1 FTE
capacity recovered
Gross labor savings
$20,077
Annual software cost
$1,800
Equivalent to recovering 0.1 full-time employees of engineering capacity.
Based on:
- 6 reviewers
- $145,000 average fully burdened employee cost
- 5 hours per reviewer per week spent on drawing reviews
- 20% estimated efficiency improvement
- 6 PDF Engineer licenses
Estimates are based on the information provided and are intended for planning purposes. Actual savings will vary based on workflow, adoption, and usage.
Plans & Pricing
Simple pricing
Test every feature on your own drawings for 30 days. Then choose one simple paid subscription per user.
30-day free trial
$25$25
per month, per user when billed annually.
Start 30-day trial
Use your own drawings and workflows. Every feature is included.
Already evaluated it? Subscribe now.
Education Access
Free for engineering students and educators
PDF Engineer is free for students, professors, instructors, and university labs with a valid .edu email address. Download the app and use the in-app education flow for mechanical drawing markups, GD&T redlines, capstone reviews, and class projects without paying for a subscription.
Frequently Asked Questions
Questions from mechanical teams evaluating PDF Engineer.
Clear answers before you roll it out.
Clear answers before you roll it out.
Engineering drawing redline software lets reviewers add visible drawing annotations, questions, and proposed changes to technical drawings. PDF Engineer focuses on mechanical drawing review with tools for GD&T feature control frames, dimensions, BOM balloons, flag notes, weld symbols, centerlines, and arrows.
Open your drawing PDF in PDF Engineer, review the details, and place notes, leaders, symbols, and callouts at the features that need attention. Save a .pdf-eng project to keep your work editable, then export a standard redlined PDF to share through your existing review process.
Yes. PDF Engineer lets you compare drawing revisions side by side with highlighted differences and a list of added, removed, and replaced text. Use the comparison tool to review changed dimensions, updated notes, and other text changes during ECO reviews, supplier updates, or revision checks.
Yes. PDF Engineer includes native GD&T tools for creating feature control frames and placing them on engineering drawings with leaders. You can communicate tolerance and datum feedback without assembling frames from generic text boxes.
Yes. BOM balloons and flag notes are built-in mechanical markup tools. Use them with leaders and drawing annotations to identify assembly items and call attention to review notes directly on the drawing.
Drawing rendering, markup creation, review, and export happen locally on your workstation. PDF Engineer does not upload engineering documents to external servers for those operations. Internet connectivity supports account management, company seat administration, subscription validation, updates, and support requests.
Download PDF Engineer and test every feature for 30 days using the drawings and review workflows your team already works with. Your drawing files stay on your machine throughout the trial.
PDF Engineer focuses on mechanical drawing redlines with native GD&T feature control frames, BOM balloons, flag notes, and other engineering annotations. Choose it when these tools fit your daily drawing reviews, and keep Acrobat or Bluebeam for other document workflows your team needs. Exported standard PDFs open in either viewer.
Yes. PDF Engineer exports standard PDF files that open in major viewers such as Acrobat, Bluebeam, and the document viewers used inside many PLM workflows.
Yes. You can paste an image file or screenshot into PDF Engineer and use the same markup tools you use on PDFs, which is useful for quick CAD views, drawing details, inspection photos, and shop-floor feedback that does not need a full PDF package.
Usually no. Most teams review drawings in PDF Engineer and then attach the redlined PDF back into their existing PLM, ERP, or document control process.
A .pdf-eng file is a project file for editable work in PDF Engineer. It preserves annotations and review state while letting teams export a standard PDF when they are ready to share or release.
Yes. PDF Engineer uses simple per-user licensing with monthly and annual billing options.
Yes. PDF Engineer is free for students and educators with a valid .edu email address, including engineering students, professors, instructors, and university labs that need a PDF editor for mechanical drawing markups.
Mechanical design, manufacturing, supplier quality, and product development teams use PDF Engineer for ECO and ECR reviews, DFM feedback, supplier clarification packages, and inspection markups.
Spend less time marking up drawings and more time engineering.
Test PDF Engineer on your own drawings for 30 days. Give your team a faster way to review, redline, and communicate changes—without sending engineering drawings to the cloud.
Full feature access • Your drawings stay local