> ## Documentation Index > Fetch the complete documentation index at: https://luminouslabs-cc5545c6-docs-main-reorder.mintlify.site/llms.txt > Use this file to discover all available pages before exploring further. # FAQ > Frequently asked questions about light token, PDA accounts, and use cases. export const lightCreateAtaCode = ['import { createAtaInterface } from "@lightprotocol/compressed-token";', "", "const ata = await createAtaInterface(", " rpc,", " payer,", " mint,", " owner", ");"].join("\n"); export const splCreateAtaCode = ['import { getOrCreateAssociatedTokenAccount } from "@solana/spl-token";', "", "const ata = await getOrCreateAssociatedTokenAccount(", " connection,", " payer,", " mint,", " owner", ");"].join("\n"); export const RentLifecycleVisualizer = () => { const [, setTime] = useState(0); const [lamports, setLamports] = useState(0); const [isRunning, setIsRunning] = useState(false); const [phase, setPhase] = useState("uninitialized"); const [hasUserClicked, setHasUserClicked] = useState(false); const [showControls, setShowControls] = useState(false); const containerRef = useRef(null); const [isHighlighted, setIsHighlighted] = useState(false); const [activeArrows, setActiveArrows] = useState([]); const [activeLines, setActiveLines] = useState([]); const [isButtonPressed, setIsButtonPressed] = useState(false); const [flyingArrows, setFlyingArrows] = useState([]); const [floatingAmounts, setFloatingAmounts] = useState([]); const [resetCount, setResetCount] = useState(0); const [timelineStarted, setTimelineStarted] = useState(false); const LAMPORTS_PER_TICK = 60; const INITIAL_RENT = 6400; const TOPUP_LAMPORTS = 800; const TOPUP_THRESHOLD = 800; const COLD_THRESHOLD = 400; const GREY = { r: 161, g: 161, b: 170 }; const RED = { r: 227, g: 89, b: 48 }; const BLUE = { r: 120, g: 140, b: 180 }; const txLines = [{ id: 0, x1: 5, y1: 20, x2: 50, y2: 50 }, { id: 1, x1: 95, y1: 15, x2: 50, y2: 50 }, { id: 2, x1: 0, y1: 50, x2: 50, y2: 50 }, { id: 3, x1: 100, y1: 55, x2: 50, y2: 50 }, { id: 4, x1: 10, y1: 85, x2: 50, y2: 50 }, { id: 5, x1: 90, y1: 90, x2: 50, y2: 50 }, { id: 6, x1: 50, y1: 0, x2: 50, y2: 50 }]; const interpolateColor = (c1, c2, t) => { const clamp = v => Math.max(0, Math.min(255, Math.round(v))); return { r: clamp(c1.r + (c2.r - c1.r) * t), g: clamp(c1.g + (c2.g - c1.g) * t), b: clamp(c1.b + (c2.b - c1.b) * t) }; }; const colorToRgba = (c, alpha = 1) => `rgba(${c.r}, ${c.g}, ${c.b}, ${alpha})`; const formatLamports = l => { if (l <= 0) return "0"; const rounded = Math.round(l / 500) * 500; return `~${rounded.toLocaleString()}`; }; const arrowIdRef = useRef(0); const flyingArrowIdRef = useRef(0); const floatingAmountIdRef = useRef(0); const triggerFlyingArrow = (amount, lineIndex) => { const id = flyingArrowIdRef.current++; setFlyingArrows(prev => [...prev, id]); setTimeout(() => { setFlyingArrows(prev => prev.filter(a => a !== id)); }, 600); const amountId = floatingAmountIdRef.current++; const line = txLines[lineIndex] || txLines[0]; setFloatingAmounts(prev => [...prev, { id: amountId, amount, x: line.x1, y: line.y1 }]); setTimeout(() => { setFloatingAmounts(prev => prev.filter(a => a.id !== amountId)); }, 800); }; const triggerHighlight = () => { setIsHighlighted(true); setTimeout(() => setIsHighlighted(false), 500); const arrowId = arrowIdRef.current++; setActiveArrows(prev => [...prev, arrowId]); setTimeout(() => { setActiveArrows(prev => prev.filter(id => id !== arrowId)); }, 500); }; const triggerTransaction = lineIndex => { setActiveLines(prev => [...prev, { id: lineIndex, startTime: Date.now() }]); setTimeout(() => { setActiveLines(prev => prev.filter(l => l.id !== lineIndex)); }, 500); }; const txLineIndexRef = useRef(0); const lastLineIndexRef = useRef(0); const getNextLineIndex = () => { const index = txLineIndexRef.current; txLineIndexRef.current = (txLineIndexRef.current + 1) % txLines.length; lastLineIndexRef.current = index; return index; }; const getAccountColor = () => { if (phase === "uninitialized") return GREY; if (phase === "cold") return BLUE; if (lamports > TOPUP_THRESHOLD) { return RED; } else if (lamports > COLD_THRESHOLD) { const t = 1 - (lamports - COLD_THRESHOLD) / (TOPUP_THRESHOLD - COLD_THRESHOLD); return interpolateColor(RED, BLUE, t); } else { return BLUE; } }; const handleTopup = () => { triggerTransaction(getNextLineIndex()); setIsButtonPressed(true); setTimeout(() => setIsButtonPressed(false), 200); if (phase === "uninitialized" || phase === "cold" || lamports === 0) { setLamports(INITIAL_RENT); setPhase("hot"); triggerHighlight(); triggerFlyingArrow(INITIAL_RENT, lastLineIndexRef.current); return; } if (lamports < TOPUP_THRESHOLD) { setLamports(l => l + TOPUP_LAMPORTS); triggerHighlight(); triggerFlyingArrow(TOPUP_LAMPORTS, lastLineIndexRef.current); } }; const txTimesRef = useRef([1.3, 2, 2.7, 3.3, 4, 4.7, 5.3, 6, 6.7, 7.3, 8, 8.7, 9.3, 10.1, 11.5, 12.8, 16, 16.7, 17.3, 18, 18.7, 19.3, 20, 20.7, 21.3, 22, 22.7, 23.3, 24, 24.7, 25.5, 26.8]); const handleReset = () => { setTime(0); setLamports(0); setPhase("uninitialized"); setIsRunning(true); setTimelineStarted(false); setActiveLines([]); setActiveArrows([]); setFlyingArrows([]); setResetCount(c => c + 1); txLineIndexRef.current = 0; arrowIdRef.current = 0; flyingArrowIdRef.current = 0; }; const handleDiamondClick = () => { if (!hasUserClicked) { setHasUserClicked(true); setIsRunning(true); setShowControls(true); } }; useEffect(() => { if (!isRunning) return; const interval = setInterval(() => { setTime(t => { const newTime = t + 0.1; if (t < 1.0 && newTime >= 1.0) { setLamports(INITIAL_RENT); setPhase("hot"); setTimelineStarted(true); triggerHighlight(); triggerTransaction(getNextLineIndex()); } txTimesRef.current.forEach(txTime => { if (newTime >= txTime && t < txTime) { triggerTransaction(getNextLineIndex()); if (phase === "cold") { setLamports(INITIAL_RENT); setPhase("hot"); triggerHighlight(); triggerFlyingArrow(INITIAL_RENT, lastLineIndexRef.current); } else if (phase === "hot") { setLamports(currentLamports => { if (currentLamports > 0 && currentLamports < TOPUP_THRESHOLD) { triggerHighlight(); triggerFlyingArrow(TOPUP_LAMPORTS, lastLineIndexRef.current); return currentLamports + TOPUP_LAMPORTS; } return currentLamports; }); } } }); if ((phase === "hot" || phase === "cold") && newTime > 0.1) { setLamports(l => { const tickAmount = LAMPORTS_PER_TICK; const newLamports = Math.max(0, l - tickAmount); if (newLamports < COLD_THRESHOLD) { setPhase("cold"); } return newLamports; }); } if (newTime >= 29) { setPhase("uninitialized"); setLamports(0); setHasUserClicked(false); setIsRunning(false); setShowControls(false); setTimelineStarted(false); txLineIndexRef.current = 0; return 0; } return newTime; }); }, 100); return () => clearInterval(interval); }, [isRunning, phase]); const accountColor = getAccountColor(); const generateDiamondDots = () => { const dots = []; const size = 5; const centerSize = 4; for (let row = -size; row <= size; row++) { const width = size - Math.abs(row); for (let col = -width; col <= width; col++) { const distFromCenter = Math.max(Math.abs(row), Math.abs(col)); const fadeProgress = distFromCenter / size; const dotSize = Math.max(0.3, centerSize * Math.pow(1 - fadeProgress, 1.5)); const opacity = Math.pow(1 - fadeProgress, 2.5); dots.push({ x: 50 + col * 6, y: 50 + row * 6, size: dotSize, opacity }); } } return dots; }; const diamondDots = generateDiamondDots(); const isLineActive = lineId => activeLines.some(l => l.id === lineId); return
{} {}
{} {txLines.map(line => { const active = isLineActive(line.id); return {} {} {active && } ; })} {} {floatingAmounts.map(({id, amount, x, y}) => +{amount.toLocaleString()} )} {}
{}
{[...Array(34).keys()].map(i => i * 3).concat([...Array(34).keys()].map(i => i * 3)).map((h, i) =>
{h}h
)}
{}
{}
0 ? "drop-shadow(0 0 25px rgba(227, 89, 48, 0.7)) drop-shadow(0 0 10px rgba(255, 150, 50, 0.8))" : "none", transition: "filter 0.15s ease" }}> {diamondDots.map((dot, i) => )} {} {!hasUserClicked &&
Press to see the Rent lifecycle over time!
}
{}
{}
{}
{activeArrows.map(arrowId => ↑ )} {flyingArrows.map(id => ↑ )}
{formatLamports(lamports)} lamports
Rent Balance
{}
; }; export const CodeCompare = ({firstCode = "", secondCode = "", firstLabel = "Light Token", secondLabel = "SPL", language = "javascript"}) => { const [sliderPercent, setSliderPercent] = useState(100); const [isDragging, setIsDragging] = useState(false); const [isAnimating, setIsAnimating] = useState(false); const [copied, setCopied] = useState(false); const containerRef = useRef(null); const animationRef = useRef(null); const firstPreRef = useRef(null); const secondPreRef = useRef(null); const [containerHeight, setContainerHeight] = useState(null); const showingFirst = sliderPercent > 50; const handleCopy = async () => { const codeToCopy = showingFirst ? firstCode : secondCode; await navigator.clipboard.writeText(codeToCopy); setCopied(true); setTimeout(() => setCopied(false), 2000); }; const highlightCode = code => { let escaped = code.replace(/&/g, "&").replace(//g, ">"); if (language === "rust") { const rustPattern = /(\/\/.*$)|(["'])(?:(?!\2)[^\\]|\\.)*?\2|\b(use|let|mut|pub|fn|struct|impl|enum|mod|const|static|trait|type|where|for|in|if|else|match|loop|while|return|self|Self|true|false|Some|None|Ok|Err|Result|Option|vec!)\b|::([a-zA-Z_][a-zA-Z0-9_]*)|&([a-zA-Z_][a-zA-Z0-9_]*)|\b([a-zA-Z_][a-zA-Z0-9_]*)\s*(?=\()|(\?)/gm; return escaped.replace(rustPattern, (match, comment, stringQuote, keyword, pathSegment, reference, func, questionMark) => { if (comment) return `${match}`; if (stringQuote) return `${match}`; if (keyword) return `${match}`; if (pathSegment) return `::${pathSegment}`; if (reference) return `&${reference}`; if (func) return `${match}`; if (questionMark) return `?`; return match; }); } const pattern = /(\/\/.*$)|(["'`])(?:(?!\2)[^\\]|\\.)*?\2|\b(const|let|var|await|async|import|from|export|return|if|else|function|class|new|throw|try|catch)\b|\.([a-zA-Z_][a-zA-Z0-9_]*)\b|\b([a-zA-Z_][a-zA-Z0-9_]*)\s*(?=\()/gm; return escaped.replace(pattern, (match, comment, stringQuote, keyword, property, func) => { if (comment) return `${match}`; if (stringQuote) return `${match}`; if (keyword) return `${match}`; if (property) return `.${property}`; if (func) return `${match}`; return match; }); }; const animateTo = target => { if (animationRef.current) cancelAnimationFrame(animationRef.current); setIsAnimating(true); const start = sliderPercent; const startTime = performance.now(); const duration = 400; const animate = currentTime => { const elapsed = currentTime - startTime; const progress = Math.min(elapsed / duration, 1); const eased = 1 - Math.pow(1 - progress, 3); const current = start + (target - start) * eased; setSliderPercent(current); if (progress < 1) { animationRef.current = requestAnimationFrame(animate); } else { setSliderPercent(target); setIsAnimating(false); animationRef.current = null; } }; animationRef.current = requestAnimationFrame(animate); }; const handleToggle = () => { animateTo(showingFirst ? 0 : 100); }; const handleMouseDown = e => { if (isAnimating) { cancelAnimationFrame(animationRef.current); setIsAnimating(false); } e.preventDefault(); setIsDragging(true); }; const handleMouseUp = () => { setIsDragging(false); }; const handleMouseMove = e => { if (!isDragging || !containerRef.current) return; const rect = containerRef.current.getBoundingClientRect(); const x = e.clientX - rect.left; const percent = Math.max(0, Math.min(100, x / rect.width * 100)); setSliderPercent(percent); }; const handleTouchMove = e => { if (!containerRef.current) return; if (isAnimating) { cancelAnimationFrame(animationRef.current); setIsAnimating(false); } const rect = containerRef.current.getBoundingClientRect(); const x = e.touches[0].clientX - rect.left; const percent = Math.max(0, Math.min(100, x / rect.width * 100)); setSliderPercent(percent); }; const handleKeyDown = e => { if (e.key === "ArrowLeft") { setSliderPercent(p => Math.max(0, p - 5)); } else if (e.key === "ArrowRight") { setSliderPercent(p => Math.min(100, p + 5)); } }; useEffect(() => { if (isDragging) { document.addEventListener("mousemove", handleMouseMove); document.addEventListener("mouseup", handleMouseUp); return () => { document.removeEventListener("mousemove", handleMouseMove); document.removeEventListener("mouseup", handleMouseUp); }; } }, [isDragging]); useEffect(() => { return () => { if (animationRef.current) cancelAnimationFrame(animationRef.current); }; }, []); useEffect(() => { const activeRef = showingFirst ? firstPreRef : secondPreRef; if (activeRef.current) { setContainerHeight(activeRef.current.scrollHeight); } }, [showingFirst]); return <>
{}
{showingFirst ? firstLabel : secondLabel}
{} {}
{}
{}
{}
{} 

              {}
{}
{}
{[0, 1, 2].map(i =>
)}
{[0, 1, 2].map(i =>
)}
; }; ## Rent Sponsorship Rent sponsorship is a built-in feature of the Light SDK’s that sponsors rent-exemption for all account types to reduce creation cost: mints, token accounts, and PDAs. This is dealt with under the hood in a way that doesn’t disrupt the UX of what your users are used to with SPL-token. | Account Creation Cost | Light | Standard Solana | | :--------------------------- | :------------------ | :-------------- | | **Mint account** | **\~0.00001 SOL** | \~0.0015 SOL | | **Associated token account** | **\~0.00001 SOL** | \~0.002 SOL | | **PDA (100-byte)** | **\~0.0000115 SOL** | \~0.0016 SOL | **Rent-exemption: sponsored by a rent sponsor PDA.** Every Solana account requires a rent-exempt balance in SOL upon creation. A rent sponsor PDA by Light Protocol pays the rent-exemption cost for the account so account creators never lock up SOL for rent. **Top-ups: paid by the fee payer.** The `feePayer` on the transaction bumps a small virtual rent balance (766 lamports by default) on each write to keep the account active (hot balance). If you're building a wallet or dApp, set your application as the fee payer and your users never pay rent or top-ups. "Cold" accounts virtual rent balance below threshold (eg 24h without write bump) get auto-compressed. The cold account's state is cryptographically preserved on the Solana ledger. Users can load a cold account into hot state in-flight when using the account again. ```text theme={null} Rent sponsor PDA Fee payer bumps pays rent-exemption virtual rent on write │ │ ▼ │ ┌─────────┐ ┌────┴────┐ │ CREATE │ ──────────────────►│ HOT │◄───┐ └─────────┘ └────┬────┘ │ │ │ no writes for │ client loads threshold │ cold → hot (e.g. 24h) │ │ │ ▼ │ ┌─────────┐ │ │ COLD │────┘ └─────────┘ ``` ## Light Token Program Light token is a high-performance token standard that is functionally equivalent to SPL, but stores mint and token accounts more efficiently. This reduces account creation cost while being more CU efficient than SPL on hot paths. **Creation Cost** | | Light-Token | SPL-Token | | :---------------- | --------------: | ---------: | | **Mint Account** | **0.00001 SOL** | 0.0015 SOL | | **Token Account** | **0.00001 SOL** | 0.002 SOL | **CU Performance** | | Light-Token | SPL-Token | | :----------------------- | ----------: | --------: | | **ATA Creation** | **4,348** | 14,194 | | **Transfer** | **312** | 4,645 | | **Transfer** (rent-free) | **1,885** | 4,645 | Yes! Light Token is deployed on devnet — start integrating today with our [Quickstart](/light-token/quickstart) and [Toolkits](/light-token/toolkits/overview). For production on mainnet, use [Compressed Tokens V1](/compressed-tokens/overview), which are live and supported by leading wallets such as Phantom and Backpack. No. The `light-token-sdk` methods are a superset of the SPL-token API. Find examples below.
Light SPL
**Get/Create ATA** getOrCreateAtaInterface() getOrCreateAssociatedTokenAccount()
**Derive ATA** getAssociatedTokenAddressInterface() getAssociatedTokenAddress()
**Transfer** transferInterface() transferChecked()
**Get Balance** getAtaInterface() getAccount()
Yes, light-token accounts can hold tokens from light, SPL, or Token 2022 mints. SPL tokens can be deposited into light-token accounts and withdrawn back to SPL token accounts via the `transferInterface` method. The token standard pays rent-exemption cost for you. To prevent griefing, "rent" is paid over time to keep an account in memory. This is dealt with under the hood in a way that doesn't disrupt the UX of what your users are used to with SPL-token. 1. A rent sponsor PDA by Light Protocol pays the rent-exemption cost for the account. 2. Transaction fee payers bump a virtual rent balance when writing to the account, which keeps the account "hot". 3. "Cold" accounts virtual rent balance below threshold (eg 24h without write bump) get auto-compressed. 4. The cold account's state is cryptographically preserved on the Solana ledger. Users can load a cold account into hot state in-flight when using the account again. The account is automatically compressed. Your tokens are cryptographically preserved as a compressed token account (rent-free). The account is loaded into hot account state in-flight when someone interacts with it again. Extensions are under development. Additional extensions can be requested. Coming soon: * MetadataPointer * TokenMetadata * InterestBearingConfig * GroupPointer * GroupMemberPointer * TokenGroup * TokenGroupMember * MintCloseAuthority * TransferFeeConfig * DefaultAccountState * PermanentDelegate * TransferHook * Pausable * ConfidentialTransferMint * ConfidentialTransferFeeConfig * ConfidentialMintBurn * **light-token**: Solana account that holds token balances of light-mints, SPL or Token 22 mints. * **Compressed token**: Compressed account storing token data. Rent-free, for storage and distribution. *** ## PDA Accounts A standard Solana PDA with sponsored rent-exemption. Seeds, bump derivation, and `invoke_signed` work the same way. Your instruction handlers for reads, updates, and closes don't change. | | Regular PDA | Light-PDA | | :------------------- | -----------: | --------------: | | **100-byte account** | \~0.0016 SOL | \~0.0000115 SOL | A compressed account with a derived address. Programs invoke the Light System program instead of the System program to create and update compressed accounts. Compressed PDAs are always compressed and require a validity proof for every read and write. | | Regular PDA | Compressed PDA | | :------------------- | -----------: | -------------: | | **100-byte account** | \~0.0016 SOL | \~0.000015 SOL | | | Light-PDA | Compressed PDA | | :------------------ | :--------------------------------------------------------------- | :------------------------------------------------------------- | | **Storage** | On-chain; auto-compresses when inactive | Always compressed | | **Validity proof** | Not required | Required for every read and write | | **Program changes** | Minimal changes. Leaves program logic mostly untouched. | Custom Logic | | **Best for** | Shared state: DeFi pools, vaults, config, program-owned accounts | Per-user state: profiles, credentials, DePIN nodes, nullifiers | No. Add `compression_info: CompressionInfo` to your state struct, derive `LightAccount` and `LightAccounts`, and add `#[light_program]` above `#[program]`. Your instruction logic for reads, updates, and closes stays the same. The client prepends a load instruction if the account is cold. The SDK sponsors rent-exemption for your Light-PDAs. After extended inactivity, the account compresses to cold state and the rent-exempt lamports return to the rent sponsor. The common path (hot accounts) has no extra overhead. 1. A rent sponsor PDA by Light Protocol pays the rent-exemption cost for the account. 2. Transaction fee payers bump a virtual rent balance when writing to the account, which keeps the account "hot". 3. "Cold" accounts virtual rent balance below threshold (eg 24h without write bump) get auto-compressed. 4. The cold account's state is cryptographically preserved on the Solana ledger. Users can load a cold account into hot state in-flight when using the account again. The account data is cryptographically preserved in compressed state. The client prepends a load instruction when someone interacts with it again — your program code doesn't change. Reads, updates, and closes work the same way regardless of whether the account is hot or cold. *** ## I don't see the question I want answered DM us [@lightprotocol on X (Twitter)](http://x.com/lightprotocol) or [Discord](https://discord.com/invite/rpddh53TeG).