Monster Scaler is a tool for D&D 5th Edition that lets you take any monster and scale it to a different Challenge Rating (CR). You can also add or remove abilities, convert between the 2014 and 2024 rule editions, and export the result in several formats.
1. Getting Started
To use Monster Scaler, you need a monster's stat block in one of the supported formats. The tool will parse the stat block, let you adjust the CR and features, and show you a live preview of the scaled result.
- Click Search to browse over 3,500 monsters from the Open5e database, select one, and click Load into Scaler, or upload/paste a stat block directly
- Use the Scaling tab to change the CR
- Use the Modifying tab to add or remove abilities
- Export the result as JSON, Markdown, PDF, PNG, or XML
2. Monster Search
Click the Search button to browse the Open5e monster database with over 3,500 monsters from the SRD, Tome of Beasts, Creature Codex, and more.
- Searching
- Type in the search bar to filter monsters by name. Results update as you type.
- Filters
- Click Filters to expand the filter panel. Available filters: CR range, AC range, Type, Size, Source, Alignment, Senses, and Legendary/Mythic toggles (click to cycle: off → include → exclude).
- Sorting
- Click the column headers (CR, Name, Type) to sort results. Click again to reverse the sort direction.
- Preview
- Click a monster in the results to see its stats in the detail panel on the right: CR, AC, HP, Speed, Senses, Resistances, Immunities, and image.
- Loading
- Click Load into Scaler in the detail panel to import the monster into the scaler. The monster is fetched from the database, converted to the scaler's format, and parsed automatically.
- Your Monsters
- If you're logged in, your saved monsters appear in the search results alongside database monsters, marked with a "My Monsters" badge.
3. Importing a Monster
Click the Upload button (which pulses until you load your first monster) or paste JSON directly into the text area at the bottom of the Input panel.
Supported Formats
- JSON - Open5e format (v1 or v2), 5eTools, Improved Initiative, or any standard D&D JSON stat block
- Markdown - Standard stat block markdown format
- PDF - Extracts monster stat blocks from PDF pages using OCR
- Images - PNG, JPG, or WebP images of stat blocks, processed via OCR
4. The Scaling Tab
The Scaling tab is where you control how the monster's numbers change. It contains the CR selectors, edition toggles, scaling mode, feature detection checkboxes, and stat adjustments.
CR Selection
The Input row shows the source CR and edition of the imported monster. The Output row is where you set the target CR and edition you want to scale to. Use the +/- buttons or the dropdown to change CR values.
When both the input and output CR and editions match, you'll see an Identity badge on the preview, meaning the monster's stats are shown exactly as imported.
4.1 Scaling Modes
- Input Mode
- Preserves the monster's proportions relative to its source CR. If the monster has 80% of the expected HP for its source CR, it will have 80% of the expected HP at the target CR. This keeps the monster's "feel" (a glass cannon stays a glass cannon).
- Benchmark Mode
- Maps the monster's position within the source CR's stat range to the same position in the target CR's range. For example, if the monster's HP is at the 60th percentile of its source range, it will be at the 60th percentile of the target range. This mode uses the full min/max ranges from the DMG/MM tables.
4.2 Edition Settings
The Input edition tells the tool which benchmark table to compare the source monster against. The Output edition tells it which benchmark table to scale the stats toward.
- 2024 - Uses the 2024 Monster Manual benchmarks (generally lower HP, tighter stat ranges)
- 2014 - Uses the 2014 DMG benchmarks (generally higher HP, wider stat ranges)
You can use different input and output editions to convert a monster between editions. For example, importing a 2014 monster and setting the output to 2024 will rescale its stats to match 2024 expectations, even at the same CR.
4.3 Features (Scaling Tab)
When you import a monster, the tool detects special traits that affect CR calculations, such as Magic Resistance, Legendary Resistance, Damage Immunity, Pack Tactics, and many more.
These checkboxes tell the scaling math which features the monster has. The scaler uses this information to account for the monster's strengths when calculating stats.
- Checking a feature means "this monster has this trait, factor it into the CR math"
- Unchecking a feature means "ignore this trait in the CR math"
These checkboxes only affect the math. They don't add or remove ability text from the stat block. To actually add or remove abilities, use the Modifying tab.
4.4 Stat Adjustments
Below the features, you'll find adjustment fields for fine-tuning individual stats after scaling. These are flat modifiers applied on top of the scaled result:
- HP, AC, ATK, DC - Add or subtract from the scaled value
- Ability Scores - Override individual scores (STR, DEX, CON, INT, WIS, CHA)
- Speed - Adjust walk, fly, swim, or burrow speeds
5. The Modifying Tab
The Modifying tab lets you add new abilities to a monster or remove existing ones. Unlike the Scaling tab's feature checkboxes (which only affect math), changes here actually modify the stat block, adding or removing ability text and adjusting the numbers to compensate.
Features are organized by category:
- HP Features - Traits that affect survivability (Regeneration, Death Save, Legendary Resistance, etc.)
- AC Features - Traits that affect defense (Magic Resistance, Parry, Flyby, etc.)
- DPR Features - Traits that affect damage output (Breath Weapon, Charge, Aura, etc.)
- ATK Features - Traits that affect hit chance (Pack Tactics, Reckless, etc.)
5.1 Adding & Removing Features
Adding a Feature
Check the box next to any feature to add it to the monster. The tool will:
- Add the ability's text to the stat block (using standard D&D wording)
- Adjust the monster's stats to account for the feature. For example, adding Regeneration will lower the monster's raw HP because the regeneration ability now covers part of the CR budget
Removing a Feature
Uncheck a feature that was detected on the imported monster to remove it. The ability text will be stripped from the stat block and the stats will increase to compensate.
5.2 Configuring Features
Some features have a Config button that lets you customize values before adding them:
- Regeneration - Set HP recovered per round
- Legendary Resistance - Set uses per day
- Breath Weapon - Set burst damage, damage type, area shape (cone/line/sphere), and saving throw type
- Swallow/Engulf - Set per-turn damage, release threshold, and damage type
- Charge - Choose between Charge, Trampling Charge, or Pounce variants, each with configurable extra damage
- Death Save - Choose between Escalating DC, Damage Threshold, Once per Rest, or Undead Fortitude variants
- Aura - Set damage and damage type
- Bonus Weapon Damage - Set bonus damage and damage type
- Damage Absorption - Set the absorbed damage type
- Rejuvenation - Customize the prevention condition text
- Sneak Attack - Set bonus damage amount
Default values scale with the target CR, so higher-CR monsters get appropriately larger numbers.
6. The Preview Panel
The Preview panel shows a live, formatted stat block of the scaled monster. It updates automatically as you change CR, edition, features, or adjustments.
- Sheet Theme
- Changes the color scheme of the stat block. Choose from 25+ themes. This affects only the preview and exports, not the app interface.
- Display Format
- Controls how the stat block text is worded: 2014 style ("Melee Weapon Attack: +X to hit") or 2024 style ("Attack Roll: +X"). Set to Auto to match the output edition. This is independent of the edition benchmarks used for scaling.
- Image
- Shows or hides the monster's image on the stat block. Drag to reposition, resize with corner handles. Only available when the monster has an image URL or you upload one.
- Background
- Choose the stat block background: Texture (parchment image), Solid (pick any color with the color picker), or Transparent (no background, useful for PNG exports with transparent backgrounds).
- Single-Column
- Forces the stat block into a single-column layout instead of the default two-column layout. Useful for narrower displays or when you prefer a vertical stat block.
6.1 Display Format
The Display Format setting controls the visual presentation of the stat block, not the math:
- 2024 format uses "Attack Roll: +X", bare dice expressions ("2d10 + 5 Slashing damage"), and "Saving Throw: DC X" style
- 2014 format uses "Melee Weapon Attack: +X to hit", averaged damage ("19 (2d10 + 8) piercing damage"), and "DC X Dexterity saving throw" style
- Auto matches whichever edition is set as the output
6.2 Background Settings
- Texture
- The classic parchment texture. Adapts to the selected theme (light or dark versions).
- Solid
- A flat color background. A color picker appears so you can choose any color. Defaults to the theme's stat block color.
- Transparent
- No background at all. When you export as PNG, the image will have a transparent background, perfect for placing the stat block over custom artwork or in other documents.
6.3 Monster Images
If the imported monster has an image_url field, the Image checkbox will be automatically checked and the image displayed on the stat block.
You can also upload your own image using the upload button (arrow icon) next to the Image checkbox. Uploaded images replace the URL and avoid cross-origin issues with exports.
When an image is displayed, you can:
- Drag to reposition within the frame
- Resize using corner handles
- Pan using the center handle
6.4 Notes
The Notes checkbox in the sheet controls toggles a freeform text area below the stat block. Use it for DM-facing notes like tactics, lore, or scaling rationale.
- Editing
- Type directly in the text area. Notes save automatically as you type.
- Persistence
- Notes are stored in the monster's JSON data. They pass through scaling unchanged and are saved to your account via Cloud Sync.
- Exports
- When the Notes checkbox is checked, notes are included in Markdown, PDF, PNG, and XML exports. JSON exports always include notes regardless of the checkbox state.
- Theming
- The notes area matches the stat block's sheet theme, including background and colors.
7. Exporting
The Export controls appear above the stat block preview. Available formats:
- JSON
- Download as a JSON file. Choose between Open5e, 5eTools Homebrew, or Improved Initiative formats.
- Markdown
- Download as a Markdown file. Choose Standard or Homebrewery format.
- Download the stat block as a PDF document.
- PNG
- Download the stat block as a high-resolution image. If the background is set to Transparent, the PNG will have a transparent background.
- XML
- Download as Fight Club 5e XML format.
8. The JSON Editor
At the bottom of the Input panel is a text area showing the monster's JSON data. You can edit this directly. Changes are automatically parsed after a short delay, or press Ctrl+Enter to parse immediately.
For larger edits, click Open Editor to open a full-screen editor.
8.1 Input / Output JSON
Above the JSON text area, you'll see Input and Output toggle buttons:
- Input
- Shows the original imported monster JSON (before scaling). Editing here changes the source monster and triggers re-scaling through the full pipeline.
- Output
- Shows the final scaled and modified monster JSON (after scaling, feature changes, and adjustments). Editing here changes the result directly without re-scaling. Useful for tweaking ability wording or making small adjustments to the final output.
9. Themes
Click the Theme button in the header to open the theme picker. Themes change the color scheme of the entire app interface. The Sheet Theme in the Preview controls changes only the stat block's colors, independently of the app theme.
Dark themes automatically use inverted background textures for readability.
10. Your Account
When you're logged in, Monster Scaler provides cloud-based features for saving, managing, and sharing your monsters. Your account ties together automatic cloud saves, a personal monster library, and the ability to share stat blocks with others.
10.1 Cloud Sync
When you're logged in, Monster Scaler automatically saves your current monster to the cloud after every change. This includes scaling, feature modifications, notes edits, and display adjustments.
- How It Works
- Changes are saved automatically with a 3-second debounce. After you stop making changes, the current state is saved to your account. A brief "Saved ✓" indicator appears in the preview panel header on each successful save.
- What's Saved
- The complete scaled monster (stats, abilities, notes) plus your display settings (theme, format, background, column layout, stat block width).
- Storage Limit
- Up to 20 monsters per account. When the limit is reached, the oldest unpinned monster is automatically removed to make room. Pin monsters you want to keep.
10.2 My Monsters
Access your saved monsters from the user menu in the header. The My Monsters modal shows all monsters saved to your account with a two-panel layout: monster list on the left, details on the right.
- Viewing Details
- Click any monster in the list to see its stats (CR, AC, HP, Speed, Senses, Resistances, Immunities), image, and notes in the detail panel.
- Loading
- Click Load into Scaler in the detail panel to open the monster in the scaler.
- Pinning
- Pin monsters to protect them from auto-deletion when you reach the 20-monster storage limit. Pinned monsters show a rotated pin icon.
- Sharing
- Click Share on a pinned monster to generate a share link. See the Sharing section for details.
- Deleting
- Click Delete to permanently remove a monster from your account.
- Export & Import
- Select monsters with checkboxes and click Export to download them as a JSON backup file. Use Import to restore monsters from a backup.
10.3 Sharing
Share a pinned monster with anyone via a short link. The recipient sees a read-only stat block with your exact theme, display settings, and notes.
- How to Share
- Open My Monsters, click a pinned monster, then click Share. The share link is copied to your clipboard. Share it via Discord, text, email, or anywhere else.
- What the Recipient Sees
- A clean, read-only stat block rendered with your chosen theme, display format, background, column layout, and notes. No editing controls are shown.
- Unsharing
- Click Share again on a shared monster to copy the link, or click Unshare in the popover to disable the link. The same link will work again if you re-share.
- Requirements
- Only pinned monsters can be shared. Unpinning a shared monster automatically unshares it.
11. Warnings & Indicators
Parse Issue Icons
After importing, you may see colored icons next to the Preview title:
- Green checkmark - No issues detected
- Yellow warning - Minor issues found (hover to see details)
- Red error - Significant parsing problems detected
HP Benchmark Warning
When scaling between editions (e.g., 2014 to 2024), a warning icon may appear next to the HP line if the monster's HP doesn't fit either edition's expected range. This usually means the source CR may be incorrect. The tool automatically corrects for common mismatches, so this warning only appears when the mismatch is unusual.
Review Markers
Shield-shaped markers appear next to ability descriptions that contain inline stat references (like "AC 15" or "10 hit points") that may need manual review after scaling. These numbers might be narrative references rather than scalable stats.
Identity Badge
Shows "Identity" when the input and output CR and editions match in Input scaling mode. This means the monster's stats are displayed exactly as imported, with no scaling applied.
12. Tips & Best Practices
- Start with Input mode for most scaling tasks. It preserves the monster's character better than Benchmark mode.
- Check the features after importing. The tool detects most common features automatically, but unusual homebrew traits may not be recognized.
- Use the Modifying tab to add thematic abilities when scaling up. A CR 5 monster scaled to CR 12 will have bigger numbers, but adding Legendary Resistance or Magic Resistance makes it feel like a proper high-CR creature.
- Switch to Output JSON to fine-tune ability wording after adding features via the Modifying tab.
- Use Transparent background when exporting PNGs for use in virtual tabletops or documents where you want the stat block to blend with the background.
- Cross-edition conversion works at the same CR. Set different input and output editions to convert a 2014 monster to 2024 stats (or vice versa) without changing its CR.