One Design, 20 Sizes: How Agencies Actually Pull It Off

Anyone who’s worked in a digital agency knows the pain: clients need display ads in dozens of formats. One creative brief can suddenly turn into requests for squares, banners, skyscrapers, leaderboards, mobile–all in unique sizes, and all needed yesterday. If you’re still manually cropping, resizing, shifting layers, and double-checking edge cases, you’re not alone. But there’s a reason agencies with the deepest client rosters rarely do this grunt work for every single asset. We’ll break down exactly how modern teams (including us at SizeIM) actually pull off the promise of one design, 20 sizes—without drowning in file versions or sacrificing brand consistency.

Why Multi-Size Ad Generation Is Non-Negotiable

For agencies managing multiple brands or high-frequency campaigns, the fragmented world of digital ads can quickly get overwhelming. Publishers and platforms demand standard rectangles (like 300×250 and 336×280), leaderboards (728×90, 970×90, 320×50), skyscrapers and banners in all orientations. The list grows: verticals, mobile breakouts, extra-large billboards.

• You face both classic browsers and mobile-only environments.
• Networks may suddenly require a new custom format the week before launch.
• Brand teams expect unwavering consistency, regardless of platform.

Our experience taught us the old way simply doesn’t scale. Designing from scratch for each format isn’t just inefficient—it erodes creative focus and endangers campaign reach. The math backs it up: each format multiplies file counts, introduces risk for errors, consumes hours, and chips away at deadlines.

What Really Breaks When You Manually Resize Ads?

From our years working with agencies and creative teams, these are the problems that repeatedly trip up workflows relying on manual resizing:

• Inconsistency: Tiny shifts creep in. A logo nudged, a call-to-action that falls too low, color mismatches. It all chips away at the client’s brand recognition in market.
• Versions Chaos: File updates for one revision spiral out—someone forgets to update the copy on all 20 versions, or just one file slips through unapproved.
• Resource Drain: It’s not uncommon for a single campaign’s resizing to eat up dozens of hours—time better spent on strategy or creative ideas.
• Lack of Scalability: Teams simply drop formats that are too much work, shrinking campaign reach and letting opportunities pass by.

The Science (and Art) Behind Designing Responsively for Ads

Getting one design to work elegantly across 20 different ad sizes means building with flexibility and systems thinking. We see it as a blend of design system discipline and real-world creative logic.

Spatial Systems: The 8-Point Grid

Consistency starts with a foundational grid. Creatives who set up layouts and templates using an 8-point base unit find it easier to scale designs up or down without layout chaos. This principle means that all elements (margins, paddings, font sizes, containers) adjust predictably when moving between rectangles, banners, or squares.

• Everything aligns and scales on multiples of eight pixels: 8, 16, 24, 32, 40, 48—easy math, clean lines.
• Brand-recognizable elements (like logos and key visuals) maintain relative balance, no matter the format switch.

Component-Based Design: Building in Modular Blocks

Instead of working up separate files for every format, we recommend thinking of ad assets as a connected system of components—headline blocks, native image modules, CTAs, safe areas, etc. These get built as variants that respond differently to space constraints:

• Orientation: Horizontal (leaderboards), vertical (skyscrapers), or square variants.
• Content Density: Compact mode for very small spaces, spacious layout for billboards or large desktop banners.
• Hierarchy: Image first, headline first, logo overlays—all systematically handled through logic, not ad-hoc guessing.

Brand Kits and Asset Centralization

We’ve watched this make or break deadlines: centralizing logos, fonts, colors, and imagery in a single “brand kit.” If you update a color or swap a logo, all assets pull the change automatically across every format. This level of asset control keeps output consistent and avoids costly last-minute rework.

Our Actual Agency Workflow (Step-by-Step)

Here’s how we tackle one design in 20 sizes using responsive frameworks, keeping things efficient and organized for any campaign, large or small:

1. Template Selection: Begin with a professionally built template—either from a robust library or create a new one mapped to the campaign’s needs. The template encodes the relationships, responsive rules, and safe design zones per format.
2. Brand Kit Integration: Plug in your brand’s asset library. That means pre-approved logos, color palette, and fonts, with alternatives for web environments where custom fonts may not render reliably.
3. Design the Master Ad: Work on a single “hero” layout, containing all essential creative, positioning, and copy elements.
4. Responsive Size Generation: Select the range of formats needed—banners, skyscrapers, rectangles, mobile leaderboards, billboards. The system reshapes and adapts the core design, generating all required variants in one go.
5. Human Review and Fine-Tuning: Automation is powerful, but we always review output. Micro-adjust cropping for hero images, tweak line breaks, check text legibility, and ensure that in unusual formats (like tall verticals), creative elements are balanced. This review step avoids machine-made awkwardness.
6. Export and Deployment: Download final assets, ready for upload to any ad network, DSP, social, or programmatic partner. Every file is versioned and consistent, reducing client anxiety and approval lag.

Best Practices When Setting Up Your Multi-Size Framework

• Document Your Rules: Write clear playbooks for what changes, what stays fixed, and how to handle edge cases by format. This helps even new designers stick to the system.
• Prioritize Legibility: Set minimum font sizes for small banners. Adjust copy length as needed per format, so nothing gets squished into unreadability.
• Assign Image Variants: Prepare alternate crops for tall versus wide formats—never just shrink or stretch images.
• Test and Compare Outputs: Before launch, review on actual devices and browsers for any rendering surprises, especially for tiny mobile spaces.
• Avoid Unnecessary Variants: Don’t create endless minor tweaks per size. Keep to main layout families (square, wide, tall) and handle exceptions with minimal variants.

Common Pitfalls We’ve Seen (and How to Avoid Them)

• Pushing Font Sizes Too Small: If scaling drops text below 10px, rewrite the copy or use another layout. It’s better to have a two-line headline that’s readable than a stylish but tiny blurb no one can see.
• Assuming One Crop Fits All: Hero images that look great in wide rectangles often lose all meaning in a square or vertical format. Always assign alternative crops for these families.
• Skipping the Manual Review: Automation gets you 90% to the finish line. Human designers catch the last 10%—awkward reflows, logo crowding, color contrast issues—so never skip the final check.
• Losing Focus on Essentials: Especially when working mobile-first, design for the smallest required ad size first. Start with the bare essentials, then elaborate for billboard and desktop versions.

Action Plan: Implementing Multi-Size Design in Your Agency

1. Audit Your Existing Process: List every pain point in your workflow, from version tracking disasters to copy-and-paste monotony. Understand where you lose time and introduce errors.
2. Create or Upgrade Your Design System: Invest in defining grids, spacing, core components, and documentation. Most friction comes from lack of systematization.
3. Run a Test Campaign: Pilot a new campaign through the process. Compare hours spent, branding consistency, and ease of collaboration between the old and new methods.
4. Train the Team: Build playbooks, quick-reference guides, and encourage everyone to treat the template as the single source of truth, not working off detached files.
5. Review and Evolve: After every project, check what worked and where adjustments are needed, and fine-tune the templates and documentation for the next round.

The Value Gained (and Why It Matters Now)

When you use a system built for smart, responsive multi-size ads, these benefits are real and immediate:

• Ad production time drops dramatically, freeing up creative hours for strategy and fresh ideas.
• Brand consistency is easy to police, even with junior designers or rotating teams.
• Agencies can expand their offering to more networks and formats with zero extra headcount.
• Clients get faster turnaround, stronger campaign reach, and fewer revision cycles.

We’ve seen agencies who switch to a systemized approach unlock capacity for more campaigns every month—without burning out staff or cutting corners on quality.

Further Reading for Creative Teams

Want to dive deeper into the world of responsive creative, display ad workflow, and multi-network campaign delivery? We’ve written tactical guides and playbooks you may find useful:

• One Ad Set, Three Networks—Here’s How
• Marketplace Ad Specs Without the Mess: A Designer’s Survival Guide
• The Science of Quick Wins: Display Ad Layouts That Perform in Days

Wrapping Up—Build for Scale, Not for Suffering

The era of manual resizing and version-driven creative traffic jams is coming to a close. Embrace design systems, template automation, and responsive frameworks to deliver multi-format campaigns that work for your agency, your client, and your sanity. If you’re ready to see what this process looks like in practice, our team at SizeIM has built these best practices into our workflow and platform for teams who want instant multi-size generation (and a lot less stress).