Yes. The Free tier is 600 requests a month at 100 requests a minute, across every endpoint in the catalogue, with no credit card. Nothing about it expires.

What happens when I hit the quota?

Requests return 429 with the limit, what you have used, and which window you tripped — nothing is queued, and nothing is charged. The monthly quota resets on the 1st (UTC). There is no rollover: unused requests do not carry into the next month.

Do failed requests use up my quota?

A 5xx does not. If a source breaks on our side, the request is excluded from your monthly count. A 4xx does count — a wrong parameter is still a request we answered. Per-minute throttling counts everything, so a retry loop is still throttled.

Which tier do I need?

Start on Free. Every response carries the remaining quota in its headers, and the dashboard reads the same number enforcement uses, so you will see the ceiling coming rather than discovering it.

How is Zapi different from RapidAPI or Apify?

Zapi focuses on a consistent REST contract — one API key, one response format, one error pattern for every source. No need to learn per-provider quirks like on traditional marketplaces, and no need to set up scraping workflows like on Apify.

What about the legality of accessing public data?

Zapi only accesses data that is publicly available without a login. Responsibility for how it is ultimately used stays with the developer — make sure your use case complies with the original source's ToS and the regulations in your operating region.

Is there an official SDK?

One: zpi-sdk, for TypeScript and JavaScript. It carries a typed error hierarchy, retries only what is safe to retry, submits bulk jobs, and verifies webhook signatures. Everything else is plain REST — cURL or any HTTP client works.

Can I request a source that isn’t in the catalogue yet?

Yes, through the community Discord, on any tier.

Mempool Space

Recommended fee tiers in sat/vB, as mempool.space's own estimator sees them.

5 endpoints1.1k calls5/5 passing

Get API key

Fees

GET/v1/finance:mempool-space/fees

slow · 1.7s1m cache

Parameters

No parameters. Call it as is.

Example response

{"project":"finance:mempool-space",  "data": {"unit":"sat/vB","dataset":"fees","hourFee":1,"provider":"mempool-space","economyFee":1,"fastestFee":1,"minimumFee":1,"halfHourFee":1  },"timestamp":"2026-08-21T02:24:38Z"}

Errors

401Missing or invalid x-api-key
404Not found or private
429Rate limit or monthly quota reached

Blocks

The last 15 blocks, decorated with mempool.space's own per-block analysis.

GET/v1/finance:mempool-space/blocks

passing · 0.8s2m cache

Parameters

Name	Type	In	Description
height	number	query	Start height. Returns that block and the 14 below it. Omit for the chain tip.

Example response

{"project":"finance:mempool-space",  "data": {"count":15,    "items": [      {"bits":386020669,"date":"2026-08-20T16:13:55.000Z","hash":"000000000000000000012494c7465e63c75e19b5ea6fac791a9e17deb9b9821b","size":1692049,"time":1787242435,"nonce":4184907309,"stale":false,"avgFee":494,"height":963330,"poolId":44,"reward":314443642,"weight":3994084,"txCount":3932,"version":637640704,        "feeRange": [          0,          0,          1        ],"poolName":"AntPool","poolSlug":"antpool","avgTxSize":430.19,"matchRate":91.02,"medianFee":1,"totalFees":1943642,"avgFeeRate":1,"difficulty":127479855693691.4,"medianTime":1787240341,"merkleRoot":"3a862f73950ada239a23900a5af2c1b096897c212c7c9c42af055837f65b1fce","similarity":null,"totalInputs":8803,"virtualSize":998521,"expectedFees":1983549,"totalOutputs":8787,"utxoSetChange":-16,"expectedWeight":3991925,"segwitTotalTxs":3127,"totalOutputAmt":916989493513,"coinbaseAddress":"37jKPSmbEGwgfacCr2nayn1wTaqMAbA94Z","segwitTotalSize":1554524,"previousBlockHash":"000000000000000000010b9a7c4cd90b904ae75d8a58b7583d24f8546bc3094d","segwitTotalWeight":3444092      },      {"bits":386020669,"date":"2026-08-20T16:10:10.000Z","hash":"000000000000000000010b9a7c4cd90b904ae75d8a58b7583d24f8546bc3094d","size":1687761,"time":1787242210,"nonce":497520903,"stale":false,"avgFee":960,"height":963329,"poolId":115,"reward":315138459,"weight":3994731,"txCount":2747,"version":537919488,        "feeRange": [          0,          0,          1        ],"poolName":"MARA Pool","poolSlug":"marapool","avgTxSize":614.29,"matchRate":97.92,"medianFee":2,"totalFees":2638459,"avgFeeRate":2,"difficulty":127479855693691.4,"medianTime":1787240064,"merkleRoot":"3b8f723ecb4bc3f5f47e8bab0964479c726633d78bf0db82bf9583ffa1cf197b","similarity":null,"totalInputs":9417,"virtualSize":998682.75,"expectedFees":2860693,"totalOutputs":6595,"utxoSetChange":-2822,"expectedWeight":3991950,"segwitTotalTxs":2474,"totalOutputAmt":880748033230,"coinbaseAddress":"32i1m6gNcSHwiPX9nfTNXVjme9j5DU8y5g","segwitTotalSize":1521952,"previousBlockHash":"000000000000000000007f37c59f2281d657b83257db8788a26572c5e7369b29","segwitTotalWeight":3331603      },      {"bits":386020669,"date":"2026-08-20T16:05:37.000Z","hash":"000000000000000000007f37c59f2281d657b83257db8788a26572c5e7369b29","size":1548015,"time":1787241937,"nonce":3099071765,"stale":false,"avgFee":906,"height":963328,"poolId":73,"reward":315854966,"weight":3993615,"txCount":3703,"version":699105280,        "feeRange": [          0,          1,          2        ],"poolName":"ViaBTC","poolSlug":"viabtc","avgTxSize":417.92,"matchRate":97.2,"medianFee":3,"totalFees":3354966,"avgFeeRate":3,"difficulty":127479855693691.4,"medianTime":1787239225,"merkleRoot":"36fbc55f29dad244a6578994f499d3ce0b39b7990fdcfb5bc61b3056468c243c","similarity":null,"totalInputs":7719,"virtualSize":998403.75,"expectedFees":3406355,"totalOutputs":8437,"utxoSetChange":718,"expectedWeight":3991908,"segwitTotalTxs":3301,"totalOutputAmt":1463544994069,"coinbaseAddress":"1PuJjnF476W3zXfVYmJfGnouzFDAXakkL4","segwitTotalSize":1358046,"previousBlockHash":"00000000000000000001ae083ea48f0a77511d01b73c4b27e8e7b77bd4363223","segwitTotalWeight":3233847      }    ],"height":963330,"dataset":"blocks","provider":"mempool-space"  },"timestamp":"2026-08-21T02:24:38Z"}

Errors

401Missing or invalid x-api-key
404Not found or private
429Rate limit or monthly quota reached

Mempool

Pending transactions and the fee-rate histogram behind them.

GET/v1/finance:mempool-space/mempool

passing · 0.4s1m cache

Parameters

No parameters. Call it as is.

Example response

{"project":"finance:mempool-space",  "data": {"count":226,    "items": [      {"vsize":93728,"feeRate":5.0099845      },      {"vsize":51246,"feeRate":2.8633094      },      {"vsize":54421,"feeRate":2      },      {"vsize":62099,"feeRate":1.005336      },      {"vsize":50137,"feeRate":0.70642203      },      {"vsize":50840,"feeRate":0.5343321      },      {"vsize":52056,"feeRate":0.5043951      },      {"vsize":52014,"feeRate":0.500987      }    ],"vsize":43778589,"dataset":"mempool","txCount":84482,"provider":"mempool-space","totalFee":8637374  },"timestamp":"2026-08-21T02:24:38Z"}

Errors

401Missing or invalid x-api-key
404Not found or private
429Rate limit or monthly quota reached

Difficulty Adjustment

Retarget progress and the difficulty change mempool.space projects from it.

GET/v1/finance:mempool-space/difficulty-adjustment

passing · 1.1s2m cache

Parameters

No parameters. Call it as is.

Example response

{"project":"finance:mempool-space",  "data": {"dataset":"difficulty-adjustment","provider":"mempool-space","timeOffset":0,"previousDate":"2026-08-08T19:35:55.000Z","previousTime":1786217755,"expectedBlocks":1768.8733333333332,"timeAvgSeconds":609,"progressPercent":86.5079365079365,"remainingBlocks":272,"difficultyChange":-1.3496349842272548,"previousRetarget":0.9889358055576736,"remainingSeconds":165528,"nextRetargetHeight":963648,"estimatedRetargetDate":"2026-08-23T00:23:26.504Z","estimatedRetargetTime":1787444607,"adjustedTimeAvgSeconds":609  },"timestamp":"2026-08-21T02:24:38Z"}

Errors

401Missing or invalid x-api-key
404Not found or private
429Rate limit or monthly quota reached

Fee Projection

The blocks mempool.space projects from the current mempool, by fee band.

GET/v1/finance:mempool-space/fee-projection

passing · 1.6s1m cache

Parameters

No parameters. Call it as is.

Example response

{"project":"finance:mempool-space",  "data": {"unit":"sat/vB","count":8,    "items": [      {"txCount":5458,        "feeRange": [          0.5004868549172347,          0.5029596412556053,          0.5058749663646964,          0.5320310255673657,          0.5946145333825157,          1.019225839528326,          30.54054054054054        ],"blockSize":1605900,"medianFee":0.5322800718132853,"totalFees":1153306,"blockIndex":0,"blockVsize":997950      },      {"txCount":3215,        "feeRange": [          0.41651705565529623,          0.41759319816873774,          0.41759319816873774,          0.43198191835004945,          0.452189949285385,          0.4853376378800108,          0.5008757456530016        ],"blockSize":2082583,"medianFee":0.4320060088865006,"totalFees":444893,"blockIndex":1,"blockVsize":997999      },      {"txCount":7165,        "feeRange": [          0.3838383838383838,          0.41651705565529623,          0.41651705565529623,          0.41651705565529623,          0.41651705565529623,          0.41656104773975494,          0.41756594724220625        ],"blockSize":1583481,"medianFee":0.4165170556552962,"totalFees":415722,"blockIndex":2,"blockVsize":997993.5      },      {"txCount":6938,        "feeRange": [          0.3832752613240418,          0.38640236792537447,          0.3962703962703963,          0.4022266115999282,          0.41651705565529623,          0.41651705565529623,          0.41651705565529623        ],"blockSize":1590664,"medianFee":0.4096576576576578,"totalFees":403880,"blockIndex":3,"blockVsize":997987      },      {"txCount":419,        "feeRange": [          0.3487544483985765,          0.3700719424460432,          0.3700719424460432,          0.3700719424460432,          0.3817427385892116,          0.3861945316001793,          0.38626378552855734        ],"blockSize":1037107,"medianFee":0.3749687560752076,"totalFees":374388,"blockIndex":4,"blockVsize":997973.5      },      {"txCount":60,        "feeRange": [          0.21212121212121213,          0.3314805457301668,          0.34197333333333335,          0.34197333333333335,          0.3493603881782091,          0.37402867234573034,          0.37490628384194596        ],"blockSize":1048847,"medianFee":0.37402867234573034,"totalFees":372841,"blockIndex":5,"blockVsize":997991.75      },      {"txCount":252,        "feeRange": [          0.2949852507374631,          0.2966292134831461,          0.2980618124672603,          0.3000475963826749,          0.30205949656750575,          0.3143631436314363,          0.350679931712486        ],"blockSize":2999333,"medianFee":0.30007109045827335,"totalFees":313519,"blockIndex":6,"blockVsize":997893.5      },      {"txCount":60988,        "feeRange": [          0.09973274888411843,          0.10364055970076447,          0.10500230998134744,          0.12021287065004276,          0.12021287065004277,          0.13023565659089015,          0.13023565659089018,          0.13023565659089018        ],"blockSize":112784000,"medianFee":0.13023565659089015,"totalFees":5163610,"blockIndex":7,"blockVsize":36822692.75      }    ],"dataset":"fee-projection","provider":"mempool-space"  },"timestamp":"2026-08-21T02:24:38Z"}

Errors

401Missing or invalid x-api-key
404Not found or private
429Rate limit or monthly quota reached

Try it

Live request with your key

const data = await client.run(  "finance:mempool-space",  "fees",  {});

Mempool Space

Recommended fee tiers in sat/vB, as mempool.space's own estimator sees them.

5 endpoints1.1k calls5/5 passing

Get API key

GET/v1/…mempool-space/fees

slow · 1.7s1m cache

Try it

Parameters

No parameters. Call it as is.

Example response

{"project":"finance:mempool-space",  "data": {"unit":"sat/vB","dataset":"fees","hourFee":1,"provider":"mempool-space","economyFee":1,"fastestFee":1,"minimumFee":1,"halfHourFee":1  },"timestamp":"2026-08-21T02:24:38Z"}

Errors

401Missing or invalid x-api-key
404Not found or private
429Rate limit or monthly quota reached

Code

const data = await client.run(  "finance:mempool-space",  "fees",  {});