Testnet - Revision history

NotATether: Add testnet4 details (does anyone know the size of testnet4?)

2025-06-22T07:45:35Z

Add testnet4 details (does anyone know the size of testnet4?)

← Older revision		Revision as of 07:45, 22 June 2025
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	Run <code>bitcoin-qt</code> or <code>bitcoind</code> with the <code>-testnet</code> flag to use the testnet (or put <code>testnet=1</code> in the <code>bitcoin.conf</code> file).		Run <code>bitcoin-qt</code> or <code>bitcoind</code> with the <code>-testnet</code> flag to use the testnet (or put <code>testnet=1</code> in the <code>bitcoin.conf</code> file).

	There have been ~~three~~ generations of testnet. Testnet2 was just the first testnet reset with a different genesis block, because people were starting to trade testnet coins for real money. ~~'''~~Testnet3~~''' is the current~~ test network~~. It was~~ introduced with the 0.7 release, ~~introduced~~ a third genesis block, a new rule to avoid the "difficulty was too high, is now too low, and transactions take too long to verify" problem, and contains blocks with edge-case transactions designed to test implementation compatibility. On 21 December 2015, SegNet was deployed to test the Wuille's Segregated Witness proposal.		There have been four generations of testnet. Testnet2 was just the first testnet reset with a different genesis block, because people were starting to trade testnet coins for real money. Testnet3 was a test network introduced with the 0.7 release, with a third genesis block, a new rule to avoid the "difficulty was too high, is now too low, and transactions take too long to verify" problem, and contains blocks with edge-case transactions designed to test implementation compatibility. On 21 December 2015, SegNet was deployed to test the Wuille's Segregated Witness proposal.

			On May 4, 2024, Jameson Lopp wrote a blog post called [https://blog.lopp.net/griefing-bitcoin-testnet/ Griefing Bitcoin's Testnet], where he describes an inherent issue with the testnet3 network that periodically resets mining difficulty, thereby allowing miners to create hundreds of blocks in a single day using [[Mining software\|mining software]] such as BFGminer. This was a catalyst in initializing the '''testnet4''' network around two months later, removing the timestamp warping special condition in the process. Testnet4 support was added in [https://github.com/bitcoin/bitcoin/blob/master/doc/release-notes/release-notes-28.0.md Bitcoin Core v28.0].

	==Differences==		==Differences==
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	==Genesis Block==		==Genesis Block==

	Testnet uses a different genesis block to the main network. You can find it [https://mempool.space/testnet/block/000000000933ea01ad0ee984209779baaec3ced90fa3f408719526f8d77f4943 here].		Testnet uses a different genesis block to the main network. You can find it [https://mempool.space/testnet4/block/00000000da84f2bafbbc53dee25a72ae507ff4914b867c565be350b0da8bf043 here]. Testnet3's genesis block can be found [https://mempool.space/testnet/block/000000000933ea01ad0ee984209779baaec3ced90fa3f408719526f8d77f4943 here].
	~~The testnet was~~ [https://github.com/gavinandresen/bitcoin-git/commit/feeb761ba07af74a7cd78b8c8f7c2a961fd9ea1c ~~reset with a new genesis block~~] for the 0.7 Bitcoin release.		Testnet2's genesis block is lcoated in this [https://github.com/gavinandresen/bitcoin-git/commit/feeb761ba07af74a7cd78b8c8f7c2a961fd9ea1c Github commit] for the 0.7 Bitcoin release.

	==Size==		==Size==
	Testnet receives less transactions than the main block chain and is typically much smaller in size. As of ~~October 2024~~, the size of the ~~data~~ on disk was 92.26 GB containing data for about 12 years worth of testnet activity.		Testnet receives less transactions than the main block chain and is typically much smaller in size. As of June 2025, the size of the testnet3 blockchain on disk was 169.28 GB containing data for about 13 years worth of testnet activity. However, testnet4 is much smaller than this amount.

	==External links==		==External links==
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	* [https://CoPay.io/ CoPay.io] wallet supports TestNet accounts		* [https://CoPay.io/ CoPay.io] wallet supports TestNet accounts

	===Faucets===		===Testnet Faucets===

	Once you're done with your test coins, it is a nice gesture to send them back to the faucets, so they become available to other developers.		Once you're done with your test coins, it is a nice gesture to send them back to the faucets, so they become available to other developers.

			====Testnet4 Faucets====

			* [https://faucet.testnet4.dev/ Testnet4.dev faucet]
			* [https://mempool.space/testnet4/faucet Mempool.space faucet] (login required)
			* [https://coinfaucet.eu/en/btc-testnet4/ Coinfaucet faucet]
			* [https://testnet4.anyone.eu.org/ Anyone.eu.org faucet]

			====Testnet3 Faucets====

			Testnet3 is still available as of the latest version of Bitcoin Core

	* [https://cryptopump.info/ Cryptopump.info Testnet Faucet]		* [https://cryptopump.info/ Cryptopump.info Testnet Faucet]
	* [http://tbtc.bitaps.com bitaps.com Testnet Faucet + double spend test tool]		* [http://tbtc.bitaps.com bitaps.com Testnet Faucet + double spend test tool]

Satoshisdojo: remove broken or inactive links

2024-10-16T17:53:38Z

remove broken or inactive links

← Older revision		Revision as of 17:53, 16 October 2024
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	==Size==		==Size==
	Testnet receives less transactions than the main block chain and is typically much smaller in size. As of ~~January 2018~~, the size of the data on disk was 14 GB containing data for about 6 years worth of testnet activity~~. Downloading this data required about 12 GB of network activity peaking at 2 MB/s rate of transfer~~.		Testnet receives less transactions than the main block chain and is typically much smaller in size. As of October 2024, the size of the data on disk was 92.26 GB containing data for about 12 years worth of testnet activity.

	==External links==		==External links==
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	* [https://mempool.space/testnet Bitcoin Testnet on mempool.space]		* [https://mempool.space/testnet Bitcoin Testnet on mempool.space]
	* [http://tbtc.bitaps.com/ Bitcoin Testnet Explorer on bitaps.com]		* [http://tbtc.bitaps.com/ Bitcoin Testnet Explorer on bitaps.com]
	* [https://www.biteasy.com/testnet/blocks Biteasy.com Testnet Blockexplorer]
	* [http://testnet.blockchain.info Blockchain.info Testnet Explorer]		* [http://testnet.blockchain.info Blockchain.info Testnet Explorer]
	* [https://test-insight.bitpay.com/ Bitcoin Testnet on insight.bitpay.com]
	* [https://www.blocktrail.com/tBTC BlockTrail Testnet Explorer, Testnet API and Testnet Faucet]
	* [https://live.blockcypher.com/btc-testnet/ BlockCypher Testnet Explorer]		* [https://live.blockcypher.com/btc-testnet/ BlockCypher Testnet Explorer]
	[[Category:Technical]]		[[Category:Technical]]

Tech1k: Add Testnet-Faucet.com to Testnet Faucets

2023-08-28T04:55:00Z

Add Testnet-Faucet.com to Testnet Faucets

← Older revision		Revision as of 04:55, 28 August 2023
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	* [http://kuttler.eu/bitcoin/btc/faucet/ nkuttler's Bitcoin Testnet Faucet]		* [http://kuttler.eu/bitcoin/btc/faucet/ nkuttler's Bitcoin Testnet Faucet]
	* [https://coinfaucet.eu/btc-testnet Coinfaucet testnet3 faucet]		* [https://coinfaucet.eu/btc-testnet Coinfaucet testnet3 faucet]
			* [https://testnet-faucet.com/btc-testnet/ Testnet-Faucet.com Bitcoin Testnet Faucet]

	Offline (2023-07-27):		Offline (2023-07-27):

Mercurytoxic: Marked faucet as offline

2023-07-27T04:26:43Z

Marked faucet as offline

← Older revision		Revision as of 04:26, 27 July 2023
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	* [http://bitcoinfaucet.uo1.net/ UO1 Testnet Faucet]		* [http://bitcoinfaucet.uo1.net/ UO1 Testnet Faucet]
	* [https://play.google.com/store/apps/details?id=com.mycelium.testnetwallet Mycelium Testnet Wallet for Android with integrated Testnet "faucet" function (Local Trader)]		* [https://play.google.com/store/apps/details?id=com.mycelium.testnetwallet Mycelium Testnet Wallet for Android with integrated Testnet "faucet" function (Local Trader)]
	* [https://testnet-faucet.mempool.co mempool.co testnet3 Faucet]
	* [http://kuttler.eu/bitcoin/btc/faucet/ nkuttler's Bitcoin Testnet Faucet]		* [http://kuttler.eu/bitcoin/btc/faucet/ nkuttler's Bitcoin Testnet Faucet]
	* [https://coinfaucet.eu/btc-testnet Coinfaucet testnet3 faucet]		* [https://coinfaucet.eu/btc-testnet Coinfaucet testnet3 faucet]

			Offline (2023-07-27):

			* [https://testnet-faucet.mempool.co mempool.co testnet3 Faucet]

	Offline (2018-09-06):		Offline (2018-09-06):

Azazar: Add cryptopump.info testnet faucet

2023-05-21T08:04:39Z

Add cryptopump.info testnet faucet

← Older revision		Revision as of 08:04, 21 May 2023
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	Once you're done with your test coins, it is a nice gesture to send them back to the faucets, so they become available to other developers.		Once you're done with your test coins, it is a nice gesture to send them back to the faucets, so they become available to other developers.
			* [https://cryptopump.info/ Cryptopump.info Testnet Faucet]
	* [http://tbtc.bitaps.com bitaps.com Testnet Faucet + double spend test tool]		* [http://tbtc.bitaps.com bitaps.com Testnet Faucet + double spend test tool]
	* [http://bitcoinfaucet.uo1.net/ UO1 Testnet Faucet]		* [http://bitcoinfaucet.uo1.net/ UO1 Testnet Faucet]

NotATether: /* Faucets */

2023-03-14T09:17:38Z

Faucets

← Older revision		Revision as of 09:17, 14 March 2023
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	* [https://testnet-faucet.mempool.co mempool.co testnet3 Faucet]		* [https://testnet-faucet.mempool.co mempool.co testnet3 Faucet]
	* [http://kuttler.eu/bitcoin/btc/faucet/ nkuttler's Bitcoin Testnet Faucet]		* [http://kuttler.eu/bitcoin/btc/faucet/ nkuttler's Bitcoin Testnet Faucet]
			* [https://coinfaucet.eu/btc-testnet Coinfaucet testnet3 faucet]

	Offline (2018-09-06):		Offline (2018-09-06):

Super-e-: /* Wallets */

2021-12-02T10:28:59Z

Wallets

← Older revision		Revision as of 10:28, 2 December 2021
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	Online testnet wallets to help you test your application.		Online testnet wallets to help you test your application.

	* [http://testnetwallet.com/ TestnetWallet.com]
	* [https://CoPay.io/ CoPay.io] wallet supports TestNet accounts		* [https://CoPay.io/ CoPay.io] wallet supports TestNet accounts

Pancyrus: Fixed some formatting issues.

2021-07-19T23:40:46Z

Fixed some formatting issues.

← Older revision		Revision as of 23:40, 19 July 2021
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	The '''testnet''' is an alternative Bitcoin [[block chain]] to be used for testing. Testnet coins are separate and distinct from actual bitcoins, and are never supposed to have any value. This allows application developers or bitcoin testers to experiment, without having to use real bitcoins or worrying about breaking the main bitcoin chain.		The '''testnet''' is an alternative Bitcoin [[block chain]] to be used for testing. Testnet coins are separate and distinct from actual bitcoins, and are never supposed to have any value. This allows application developers or bitcoin testers to experiment, without having to use real bitcoins or worrying about breaking the main bitcoin chain.

	Run bitcoin-qt or bitcoind with the -testnet flag to use the testnet (or put testnet=1 in the bitcoin.conf file).		Run <code>bitcoin-qt</code> or <code>bitcoind</code> with the <code>-testnet</code> flag to use the testnet (or put <code>testnet=1</code> in the <code>bitcoin.conf</code> file).

	There have been three generations of testnet. Testnet2 was just the first testnet reset with a different genesis block, because people were starting to trade testnet coins for real money. '''Testnet3''' is the current test network. It was introduced with the 0.7 release, introduced a third genesis block, a new rule to avoid the "difficulty was too high, is now too low, and transactions take too long to verify" problem, and contains blocks with edge-case transactions designed to test implementation compatibility. On 21 December 2015, SegNet was deployed to test the Wuille's Segregated Witness proposal.		There have been three generations of testnet. Testnet2 was just the first testnet reset with a different genesis block, because people were starting to trade testnet coins for real money. '''Testnet3''' is the current test network. It was introduced with the 0.7 release, introduced a third genesis block, a new rule to avoid the "difficulty was too high, is now too low, and transactions take too long to verify" problem, and contains blocks with edge-case transactions designed to test implementation compatibility. On 21 December 2015, SegNet was deployed to test the Wuille's Segregated Witness proposal.

Pancyrus: Fixed some formatting and grammatical issues.

2021-07-19T23:39:37Z

Fixed some formatting and grammatical issues.

Jsarenik: /* Genesis Block */ Change link to mempool.space

2021-06-06T20:19:28Z

Genesis Block: Change link to mempool.space

← Older revision		Revision as of 20:19, 6 June 2021
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	==Genesis Block==		==Genesis Block==

	Testnet uses a different genesis block to the main network. You can find it [https://~~www~~.~~biteasy.com~~/testnet/~~blocks~~/000000000933ea01ad0ee984209779baaec3ced90fa3f408719526f8d77f4943 ~~here] or [http://blockexplorer.com/testnet/b/0~~ here].		Testnet uses a different genesis block to the main network. You can find it [https://mempool.space/testnet/block/000000000933ea01ad0ee984209779baaec3ced90fa3f408719526f8d77f4943 here].
	The testnet was [https://github.com/gavinandresen/bitcoin-git/commit/feeb761ba07af74a7cd78b8c8f7c2a961fd9ea1c reset with a new genesis block] for the 0.7 bitcoin release.		The testnet was [https://github.com/gavinandresen/bitcoin-git/commit/feeb761ba07af74a7cd78b8c8f7c2a961fd9ea1c reset with a new genesis block] for the 0.7 bitcoin release.

← Older revision		Revision as of 23:39, 19 July 2021
Line 1:		Line 1:
	The '''testnet''' is an alternative Bitcoin [[block chain]], to be used for testing. Testnet coins are separate and distinct from actual bitcoins, and are never supposed to have any value. This allows application developers or bitcoin testers to experiment, without having to use real bitcoins or worrying about breaking the main bitcoin chain.		The '''testnet''' is an alternative Bitcoin [[block chain]] to be used for testing. Testnet coins are separate and distinct from actual bitcoins, and are never supposed to have any value. This allows application developers or bitcoin testers to experiment, without having to use real bitcoins or worrying about breaking the main bitcoin chain.

	Run bitcoin-qt or bitcoind with the -testnet flag to use the testnet (or put testnet=1 in the bitcoin.conf file).		Run bitcoin-qt or bitcoind with the -testnet flag to use the testnet (or put testnet=1 in the bitcoin.conf file).

	There have been three generations of testnet. Testnet2 was just the first testnet reset with a different genesis block, because people were starting to trade testnet coins for real money. '''Testnet3''' is the current test network. It was introduced with the 0.7 release, introduced a third genesis block, a new rule to avoid the "difficulty was too high, is now too low, and transactions take too long to verify" problem, and contains blocks with edge-case transactions designed to test implementation compatibility. On ~~the~~ December ~~21 of~~ 2015 SegNet was deployed, to test the Wuille's Segregated Witness proposal.		There have been three generations of testnet. Testnet2 was just the first testnet reset with a different genesis block, because people were starting to trade testnet coins for real money. '''Testnet3''' is the current test network. It was introduced with the 0.7 release, introduced a third genesis block, a new rule to avoid the "difficulty was too high, is now too low, and transactions take too long to verify" problem, and contains blocks with edge-case transactions designed to test implementation compatibility. On 21 December 2015, SegNet was deployed to test the Wuille's Segregated Witness proposal.

	==Differences==		==Differences==
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	* Default RPC connection port is 18332 (instead of 8332)		* Default RPC connection port is 18332 (instead of 8332)
	* Bootstrapping uses different DNS seeds.		* Bootstrapping uses different DNS seeds.
	* A different value of ADDRESSVERSION field ensures no testnet Bitcoin addresses will work on the production network. (0x6F rather than 0x00)		* A different value of <code>ADDRESSVERSION</code> field ensures no testnet Bitcoin addresses will work on the production network. (<code>0x6F</code> rather than <code>0x00</code>)
	* The protocol message header bytes are 0x0B110907 (instead of 0xF9BEB4D9)		* The protocol message header bytes are <code>0x0B110907</code> (instead of <code>0xF9BEB4D9</code>)
	* Minimum [[difficulty]] of 1.0 on testnet is equal to difficulty of 0.5 on mainnet. This means that the mainnet-equivalent of any testnet difficulty is half the testnet difficulty. In addition, if no block has been found in 20 minutes, the difficulty automatically resets back to the minimum for a single block, after which it returns to its previous value.		* Minimum [[difficulty]] of 1.0 on testnet is equal to difficulty of 0.5 on mainnet. This means that the mainnet-equivalent of any testnet difficulty is half the testnet difficulty. In addition, if no block has been found in 20 minutes, the difficulty automatically resets back to the minimum for a single block, after which it returns to its previous value.
	* A new genesis block		* A new genesis block
	* The IsStandard() check is disabled so that non-standard transactions can be experimented with.		* The <code>IsStandard()</code> check is disabled so that non-standard transactions can be experimented with.

	==Genesis Block==		==Genesis Block==

	Testnet uses a different genesis block to the main network. You can find it [https://mempool.space/testnet/block/000000000933ea01ad0ee984209779baaec3ced90fa3f408719526f8d77f4943 here].		Testnet uses a different genesis block to the main network. You can find it [https://mempool.space/testnet/block/000000000933ea01ad0ee984209779baaec3ced90fa3f408719526f8d77f4943 here].
	The testnet was [https://github.com/gavinandresen/bitcoin-git/commit/feeb761ba07af74a7cd78b8c8f7c2a961fd9ea1c reset with a new genesis block] for the 0.7 ~~bitcoin~~ release.		The testnet was [https://github.com/gavinandresen/bitcoin-git/commit/feeb761ba07af74a7cd78b8c8f7c2a961fd9ea1c reset with a new genesis block] for the 0.7 Bitcoin release.

	==Size==		==Size==
	Testnet receives less transactions than the main block chain and is typically much smaller in size. As of January 2018 the size of the data on disk was ~~14GB,~~ containing data for about 6 years worth of testnet activity. Downloading this data required about ~~12GB~~ of network activity peaking at ~~2MB~~/s rate of transfer.		Testnet receives less transactions than the main block chain and is typically much smaller in size. As of January 2018, the size of the data on disk was 14 GB containing data for about 6 years worth of testnet activity. Downloading this data required about 12 GB of network activity peaking at 2 MB/s rate of transfer.

	==External links==		==External links==